Ampicillin Capsules

Ampicillin Capsules, USP

To reduce the development of drug-resistant bacteria and maintain the effectiveness of ampicillin and other antibacterial drugs, ampicillin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

Ampicillin Capsules Description

Ampicillin trihydrate is a semisynthetic penicillin derived from the basic penicillin nucleus, 6- aminopenicillanic acid. Ampicillin is designated chemically as (2S, 5R, 6R)-6-[(R)-2-Amino-2-phenylacetamido]-3,3- dimethyl-7-oxo-4-thia-1-azabicyclo [3.2.0] heptane-2- carboxylic acid. Its structural formula is:

Ampicillin Capsules, USP for oral administration provide ampicillin trihydrate equivalent to 250 mg and 500 mg ampicillin. Inactive ingredients: black iron oxide, gelatin, magnesium stearate and titanium dioxide.

Ampicillin Capsules - Clinical Pharmacology

Ampicillin is bactericidal at low concentrations and is clinically effective not only against the gram-positive organisms usually susceptible to penicillin G but also against a variety of gram-negative organisms. It is stable in the presence of gastric acid and is well absorbed from the gastrointestinal tract. It diffuses readily into most body tissues and fluids; however, penetration into the cerebrospinal fluid and brain occurs only with meningeal inflammation. Ampicillin is excreted largely unchanged in the urine; its excretion can be delayed by concurrent administration of probenecid which inhibits the renal tubular secretion of ampicillin. In blood serum, ampicillin is the least bound of all the penicillins; an average of about 20 percent of the drug is bound to plasma proteins as compared to 60 to 90 percent of the other penicillins. The administration of 500 mg dose of Ampicillin Capsules results in an average peak blood serum level of approximately 3.0 mcg/mL.

Microbiology: While in vitro studies have demonstrated the susceptibility of most strains of the following organisms, clinical efficacy for infections other than those included in the INDICATIONS AND USAGE section has not been documented.

GRAM-POSITIVE – strains of alpha- and beta-hemolytic streptococci, Streptococcus pneumoniae, those strains of staphylococci, which do not produce penicillinase, Clostridium sp., Bacillus anthracis, Corynebacterium xeroses, and most strains of enterococci.

GRAM-NEGATIVE – Hemophilus influenzae; Neisseria gonorrhoeae and N. Meningitides; Proteus mirabilis, and many strains of Salmonella (including S. typhosa), Shigella, and Escherichia coli.

NOTE: Ampicillin is inactivated by penicillinase and therefore is ineffective against penicillinase-producing organisms including certain strains of staphylococci, Pseudomonas aeruginosa, P. Vulgaris, Klebsiella pneumoniae, Enterobacter aerogenes, and some strains of E. coli. Ampicillin is not active against Rickettsia, Mycoplasma, and “large viruses” (Miyagawanella).

TESTING FOR SUSCEPTIBILITY: The invading organism should be cultured and its susceptibility demonstrated as a guide to therapy. If the Kirby-Bauer method of disc susceptibility is used, a 10 mcg ampicillin disc should be used to determine the relative in vitro susceptibility.

Indications and Usage for Ampicillin Capsules

Ampicillin Capsules, USP are indicated in the treatment of infections caused by susceptible strains of the designated organism listed below:

INFECTIONS OF THE GENITOURINARY TRACT INCLUDING GONORRHEA: E. coli, P. mirabilis, enterococci, Shigella, S. typhosa and other Salmonella, and nonpenicillinaseproducing N. gonorrhoeae.

INFECTIONS OF THE RESPIRATORY TRACT: Nonpenicillinase- producing H. influenzae and staphylococci, and streptococci including streptococcus pneumoniae.

INFECTIONS OF THE GASTROINTESTINAL TRACT:

Shigella, S. typhosa and other Salmonella, E. coli, P. mirabilis, and enterococci.

MENINGITIS: N. Meningitides.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of ampicillin and other antibacterial drugs, ampicillin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Bacteriology studies to determine the causative organisms and their susceptibility to ampicillin should be performed. Therapy may be instituted prior to the results of susceptibility testing.

Contraindications

A history of a previous hypersensitivity reaction to any of the penicillins is a contraindication. Ampicillin is also contraindicated in infections caused by penicillinase-producing organisms.

Warnings

SERIOUS AND OCCASIONAL FATAL HYPERSENSITIVITY (ANAPHYLACTOID) REACTIONS HAVE BEEN REPORTED IN PATIENTS ON PENICILLIN THERAPY. ALTHOUGH ANAPHYLAXIS IS MORE FREQUENT FOLLOWING PARENTERAL ADMINISTRATION, IT HAS OCCURRED IN PATIENTS ON ORAL PENICILLINS. THESE REACTIONS ARE MORE LIKELY TO OCCUR IN INDIVIDUALS WITH A HISTORY OF PENICILLIN HYPERSENSITIVITY AND/OR A HISTORY OF SENSITIVITY TO MULTIPLE ALLERGENS.

THERE HAVE BEEN REPORTS OF INDIVIDUALS WITH A HISTORY OF PENICILLIN HYPERSENSITIVITY WHO HAVE EXPERIENCED SEVERE HYPERSENSITIVITY REACTIONS WHEN TREATED WITH CEPHALOSPORINS. BEFORE INITIATING THERAPY WITH ANY PENICILLIN, CAREFUL INQUIRY SHOULD BE MADE CONCERNING PREVIOUS HYPERSENSITIVITY REACTIONS TO PENICILLINS, CEPHALOSPORINS, AND OTHER ALLERGENS. IF AN ALLERGIC REACTION OCCURS, THE DRUG SHOULD BE DISCONTINUED AND APPROPRIATE THERAPY INSTITUTED. SERIOUS ANAPHYLACTOID REACTIONS REQUIRE IMMEDIATE EMERGENCY TREATMENT WITH EPINEPHRINE. OXYGEN, INTRAVENOUS STEROIDS, AND AIRWAY MANAGEMENT, INCLUDING INTUBATION, SHOULD ALSO BE ADMINISTERED AS INDICATED.

Pseudomembranous colitis has been reported with nearly all antibacterial agents, including ampicillin, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of antibacterial agents.

Treatment with antibacterial agents alters the normal flora of the colon and may permit overgrowth of clostridia. Studies indicate that a toxin produced by clostridium difficile, is one primary cause of “antibiotic-associated colitis”.

After the diagnosis of pseudomembranous colitis has been established, therapeutic measures should be initiated. Mild cases of pseudomembranous colitis usually respond to drug discontinuation alone. In moderate to severe cases, consideration should be given to management with fluids and electrolytes, protein supplementation and treatment with an antibacterial drug clinically effective against C. difficile colitis.

Precautions

General

Prolonged use of antibiotics may promote the overgrowth of nonsusceptible organisms, including fungi. Should superinfection occur, appropriate measures should be taken.

Patients with gonorrhea who also have syphilis should be given additional appropriate parenteral penicillin treatment.

Treatment with ampicillin does not preclude the need for surgical procedures, particularly in staphylococcal infections.

Prescribing ampicillin in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

Information For The Patient

1. The patient should inform the physician of any history of sensitivity to allergens, including previous hypersensitivity reactions to penicillins and cephalosporins (see WARNINGS).


2. The patient should discontinue ampicillin and contact the physician immediately if any side effect occurs (see WARNINGS).


3. Ampicillin should be taken with a full glass (8 oz) of water, one-half hour before or two hours after meals.


4. Diabetic patients should consult with the physician before changing diet or dosage of diabetes medication (see PRECAUTIONS–Drug/Laboratory Test Interactions).


5. Patients should be counseled that antibacterial drugs including ampicillin should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When ampicillin is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may: (1) decrease the effectiveness of the immediate treatment, and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by ampicillin or other antibacterial drugs in the future.

Laboratory Tests

In prolonged therapy, and particularly with high dosage regimens, periodic evaluation of the renal, hepatic, and hematopoietic systems is recommended.

In streptococcal infections, therapy, must be sufficient to eliminate the organism (10 days minimum); otherwise the sequelae of streptococcal disease may occur. Cultures should be taken following completion of treatment to determine whether streptococci have been eradicated.

Cases of gonococcal infection with a suspected lesion of syphilis should have darkfield examinations ruling out syphilis before receiving ampicillin. Patients who do not have suspected lesions of syphilis and are treated with ampicillin should have a follow-up serologic test for syphilis each month for four months to detect syphilis that may have been masked for treatment for gonorrhea.

Drug Interactions

When administered concurrently, the following drugs may interact with ampicillin.

ALLOPURINOL: Increased possibility of skin rash, particularly in hyperuricemic patients may occur.

BACTERIOSTATIC ANTIBIOTICS: Chloramphenicol, erythromycins, sulfonamides, or tetracyclines may interfere with the bactericidal effect of penicillins. This has been demonstrated in vitro; however, the clinical significance of this interaction is not well-documented.

ORAL CONTRACEPTIVES: May be less effective and increased breakthrough bleeding may occur.

PROBENECID: May decrease renal tubular secretion of ampicillin resulting in increased blood levels and/or ampicillin toxicity.

Drug/Laboratory Test Interaction

After treatment with ampicillin, a false-positive reaction for glucose in the urine may occur with copper sulfate tests (Benedict’s solution, Fehling’s solution, or Clinitest® tablets) but not with enzyme based tests such as Clinistix® and Tes-Tape®.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Long-term studies in animals have not been performed to evaluate carcinogenesis, mutagenesis, or impairment of fertility in males or females.

Pregnancy

Teratogenic Effects

Category B

Reproduction studies in animals have revealed no evidence of impaired fertility or harm to the fetus due to penicillin. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, penicillin should be used during pregnancy only if clearly needed.

Labor and Delivery

Oral ampicillin-class antibiotics are poorly absorbed during labor. Studies in guinea pigs showed that intravenous administration of ampicillin slightly decreased the uterine tone and frequency of contractions, but moderately increased the height and duration of contractions. However, it is not known whether use of these drugs in humans during labor or delivery has immediate or delayed adverse effects on the fetus, prolongs the duration of labor, or increases the likelihood that forceps delivery or other obstetrical intervention or resuscitation of the newborn will be necessary.

Nursing Mothers

Ampicillin-class antibiotics are excreted in milk. Ampicillin used by nursing mothers may lead to sensitization of infants; therefore, a decision should be made whether to discontinue nursing or to discontinue ampicillin, taking into account the importance of the drug to the mother.

Pediatric Use

Penicillins are excreted primarily unchanged by the kidney; therefore, the incompletely developed renal function in neonates and young infants will delay the excretion of penicillin. Administration to neonates and young infants should be limited to the lowest dosage compatible with an effective therapeutic regimen (see DOSAGE AND ADMINISTRATION).

Adverse Reactions

As with other penicillins, it may be expected that untoward reactions will be essentially limited to sensitivity phenomena. They are more likely to occur in individuals who have previously demonstrated hypersensitivity to penicillin and in those with a history of allergy, asthma, hay fever, or urticaria.

The following adverse reactions have been reported as associated with the use of ampicillin:

GASTROINTESTINAL: glossitis, stomatitis, nausea, vomiting, enterocolitis, pseudomembranous colitis, and diarrhea. These reactions are usually associated with oral dosage forms of the drugs.

HYPERSENSITIVITY REACTIONS: An erythematous, mildly pruritic, maculopapular skin rash has been reported fairly frequently . The rash, which usually does not develop within the first week of therapy, may cover the entire body including the soles, palms, and oral mucosa. The eruption usually disappears in three to seven days. Other hypersensitivity reactions that have been reported are: skin rash, pruritus, urticaria, erythema multiforme, and an occasional case of exfoliative dermatitis. Anaphylaxis is the most serious reaction experienced and has usually been associated with the parenteral dosage form of the drug.

NOTE: Urticaria, other skin rashes, and serum sicknesslike reactions may be controlled by antihistamines, and, if necessary, systemic corticosteroids. Whenever such reactions occur, ampicillin should be discontinued unless, in the opinion of the physician, the condition being treated is life-threatening, and amenable only to ampicillin therapy. Serious anaphylactoid reactions require emergency measures (see WARNINGS).

LIVER: Moderate elevation in serum glutamic oxaloacetic transaminase (SGOT) has been noted, but the significance of this finding is unknown.

HEMIC AND LYMPHATIC SYSTEMS: Anemia, thrombocytopenia, thrombocytopenic purpura, eosinophilia, leukopenia, and agranulocytosis have been reported during therapy with penicillins. These reactions are usually reversible on discontinuation of therapy and are believed to be hypersensitivity phenomena.

Other adverse reactions that have been reported with the use of ampicillin are laryngeal stridor and high fever. An occasional patient may complain of sore mouth or tongue as with any oral penicillin preparation.

(See Reverse)

Overdosage

In case of overdosage, discontinue medication, treat symptomatically and institute supportive measures as required. In patients with renal function impairment, ampicillin-class antibiotics can be removed by hemodialysis but not by peritoneal dialysis.

Ampicillin Capsules Dosage and Administration

ADULTS AND CHILDREN WEIGHING OVER 20 KG:

For genitourinary or gastrointestinal tract infections other than gonorrhea in men and women, the usual dose is 500 mg qid in equally spaced doses; severe or chronic infections may require larger doses. For the treatment of gonorrhea in both men and women, a single oral dose of 3.5 grams of ampicillin administered simultaneously with 1 gram of probenecid is recommended. Physicians are cautioned to use no less than the above recommended dosage for the treatment of gonorrhea. Follow-up cultures should be obtained from the original site(s) of infection 7 to 14 days after therapy. In women, it is also desirable to obtain culture test-of-cure from both the endocervical and anal canals. Prolonged intensive therapy is needed for complications such as prostatitis and epididymitis.

For respiratory tract infections, the usual dose is 250 mg qid in equally spaced doses.

CHILDREN WEIGHING 20 KG OR LESS:

For genitourinary or gastrointestinal tract infections, the usual dose is 100 mg/kg/day total, qid in equally divided and spaced doses. For respiratory infections, the usual dose is 50 mg/kg/day total, in equally divided and spaced doses three to four times daily. Doses for children should not exceed doses recommended for adults.

ALL PATIENTS, IRRESPECTIVE OF AGE AND WEIGHT:

Larger doses may be required for severe or chronic infections. Although ampicillin is resistant to degradation by gastric acid, it should be administered at least one-half hour before or two hours after meals for maximal absorption. Except for the single dose regimen for gonorrhea referred to above, therapy should be continued for a minimum of 48 to 72 hours after the patient becomes asymptomatic or evidence of bacterial eradication has been obtained. In infections caused by hemolytic strains of streptococci, a minimum of 10 days’ treatment is recommended to guard against the risk of rheumatic fever of glomerulonephritis (see PRECAUTIONS–Laboratory Tests). In the treatment of chronic urinary or gastrointestinal infections, frequent bacteriologic and clinical appraisal is necessary during therapy and may be necessary for several months afterwards. Stubborn infections may require treatment for several weeks. Smaller doses than those indicated above should not be used.

How is Ampicillin Capsules Supplied

Ampicillin Capsules, USP: Each capsule, for oral administration, contains ampicillin trihydrate equivalent to 250 mg or 500 mg ampicillin, and are supplied as:

250 mg: white, opaque, hard gelatin capsules, imprinted in black ink GG 850/GG 850.

NDC 0781-2144-01 in bottles of 100

NDC 0781-2144-05 in bottles of 500

500 mg: white, opaque, hard gelatin capsules, imprinted in black ink GG 851/GG 851.

NDC 0781-2145-01 in bottles of 100

NDC 0781-2145-05 in bottles of 500

Store at 20°-25°C (68°- 77°F) (see USP Controlled Room Temperature).

Dispense in a tight container.

Rev. 11-2006

8077

399658

Manufactured in Austria by Sandoz GmbH

for Sandoz Inc., Princeton, NJ 08540

mg Label

NDC 0781-2144-01

Ampicillin

Capsules, USP

250 mg

Rx only

100 Capsules

SANDOZ

mg Label

NDC 0781-2145-01

Ampicillin

Capsules, USP

500 mg

Rx only

100 Capsules

SANDOZ

AMPICILLIN  ampicillin  capsule

Product Information Product Type HUMAN PRESCRIPTION DRUG NDC Product Code (Source) 0781-2144 Route of Administration ORAL DEA Schedule

Active Ingredient/Active Moiety Ingredient Name Basis of Strength Strength AMPICILLIN TRIHYDRATE (AMPICILLIN) AMPICILLIN 250 mg

Inactive Ingredients Ingredient Name Strength MAGNESIUM STEARATE   TITANIUM DIOXIDE   GELATIN   FERROSOFERRIC OXIDE   ISOPROPYL ALCOHOL   BUTYL ALCOHOL   PROPYLENE GLYCOL   POTASSIUM HYDROXIDE   AMMONIA   ALCOHOL   SHELLAC

Product Characteristics Color WHITE (opaque) Score no score Shape CAPSULE Size 18mm Flavor Imprint Code GG850;GG850 Contains

Packaging # NDC Package Description Multilevel Packaging 1 0781-2144-01 100 CAPSULE In 1 BOTTLE None 2 0781-2144-05 500 CAPSULE In 1 BOTTLE None

Marketing Information
Marketing Category	Application Number or Monograph Citation	Marketing Start Date	Marketing End Date
ANDA	ANDA064082	08/29/1995

AMPICILLIN  ampicillin  capsule

Product Information Product Type HUMAN PRESCRIPTION DRUG NDC Product Code (Source) 0781-2145 Route of Administration ORAL DEA Schedule

Active Ingredient/Active Moiety Ingredient Name Basis of Strength Strength AMPICILLIN TRIHYDRATE (AMPICILLIN) AMPICILLIN 500 mg

Inactive Ingredients Ingredient Name Strength MAGNESIUM STEARATE   TITANIUM DIOXIDE   GELATIN   FERROSOFERRIC OXIDE   ISOPROPYL ALCOHOL   BUTYL ALCOHOL   PROPYLENE GLYCOL   POTASSIUM HYDROXIDE   AMMONIA   ALCOHOL   SHELLAC

Product Characteristics Color WHITE (opaque) Score no score Shape CAPSULE Size 22mm Flavor Imprint Code GG851;GG851 Contains

Packaging # NDC Package Description Multilevel Packaging 1 0781-2145-01 100 CAPSULE In 1 BOTTLE None 2 0781-2145-05 500 CAPSULE In 1 BOTTLE None

Marketing Information
Marketing Category	Application Number or Monograph Citation	Marketing Start Date	Marketing End Date
ANDA	ANDA064082	08/29/1995

Labeler - Sandoz Inc (110342024)

Revised: 01/2012Sandoz Inc

Zonisamide Capsules

Zonisamide Capsules USP

Rx Only

Zonisamide Capsules Description

Zonisamide USP is an antiseizure drug chemically classified as a sulfonamide and unrelated to other antiseizure agents. The active ingredient is zonisamide USP, 1,2-benzisoxazole-3-methanesulfonamide. The empirical formula is C8H8N2O3S with a molecular weight of 212.23. Zonisamide USP is a white powder, pKa = 10.2, and is moderately soluble in water (0.80 mg/mL) and 0.1 N HCl (0.50 mg/mL).

The chemical structure is:

Zonisamide is supplied for oral administration as capsules containing 25 mg, 50 mg or 100 mg zonisamide USP. Each capsule contains the labeled amount of zonisamide USP plus the following inactive ingredients: microcrystalline cellulose, hydrogenated vegetable oil, sodium lauryl sulfate, gelatin and colorants. The printed capsule shell of the different strengths is made from the following ingredients:

25 mg – D&C Red #28, FD&C Blue #1, gelatin and titanium dioxide

50 mg – D&C Yellow #10, FD&C Blue #1, FD&C Red #40, gelatin and titanium dioxide

100 mg - D&C Yellow #10, FD&C Blue #1, FD&C Yellow #6, gelatin and titanium dioxide

The dyes used in the printing ink are FD&C Blue #1, FD&C Blue #2, FD&C Red #40, D&C Yellow #10 aluminium lake and iron oxide black. Additionally, the printing ink also contains n-butyl alcohol, ethanol, methanol, propylene glycol and shellac.

Zonisamide Capsules - Clinical Pharmacology

Mechanism of Action:

The precise mechanism(s) by which zonisamide exerts its antiseizure effect is unknown. Zonisamide demonstrated anticonvulsant activity in several experimental models. In animals, zonisamide was effective against tonic extension seizures induced by maximal electroshock but ineffective against clonic seizures induced by subcutaneous pentylenetetrazol. Zonisamide raised the threshold for generalized seizures in the kindled rat model and reduced the duration of cortical focal seizures induced by electrical stimulation of the visual cortex in cats. Furthermore, zonisamide suppressed both interictal spikes and the secondarily generalized seizures produced by cortical application of tungstic acid gel in rats or by cortical freezing in cats. The relevance of these models to human epilepsy is unknown.

Zonisamide may produce these effects through action at sodium and calcium channels. In vitro pharmacological studies suggest that zonisamide blocks sodium channels and reduces voltage-dependent, transient inward currents (T-type Ca2+ currents), consequently stabilizing neuronal membranes and suppressing neuronal hypersynchronization. In vitro binding studies have demonstrated that zonisamide binds to the GABA/benzodiazepine receptor ionophore complex in an allosteric fashion which does not produce changes in chloride flux. Other in vitro studies have demonstrated that zonisamide (10 to 30 mcg/mL) suppresses synaptically-driven electrical activity without affecting postsynaptic GABA or glutamate responses (cultured mouse spinal cord neurons) or neuronal or glial uptake of [3H]-GABA (rat hippocampal slices). Thus, zonisamide does not appear to potentiate the synaptic activity of GABA. In vivo microdialysis studies demonstrated that zonisamide facilitates both dopaminergic and serotonergic neurotransmission. Zonisamide is a carbonic anhydrase inhibitor. The contribution of this pharmacological action to the therapeutic effects of zonisamide is unknown. However, as a carbonic anhydrase inhibitor, zonisamide may cause metabolic acidosis (see WARNINGS, Metabolic Acidosis subsection).

Pharmacokinetics:

Following a 200 to 400 mg oral zonisamide dose, peak plasma concentrations (range: 2 to 5 mcg/mL) in normal volunteers occur within 2 to 6 hours. In the presence of food, the time to maximum concentration is delayed, occurring at 4 to 6 hours, but food has no effect on the bioavailability of zonisamide.

Zonisamide extensively binds to erythrocytes, resulting in an eight-fold higher concentration of zonisamide in red blood cells (RBC) than in plasma. The pharmacokinetics of zonisamide are dose proportional in the range of 200 to 400 mg, but the Cmax and AUC increase disproportionately at 800 mg, perhaps due to saturable binding of zonisamide to RBC. Once a stable dose is reached, steady state is achieved within 14 days. The elimination half-life of zonisamide in plasma is about 63 hours. The elimination half-life of zonisamide in RBC is approximately 105 hours.

The apparent volume of distribution (V/F) of zonisamide is about 1.45 L/kg following a 400 mg oral dose. Zonisamide, at concentrations of 1.0 to 7.0 mcg/mL, is approximately 40% bound to human plasma proteins. Protein binding of zonisamide is unaffected in the presence of therapeutic concentrations of phenytoin, phenobarbital or carbamazepine.

Metabolism and Excretion:

Following oral administration of 14C-zonisamide to healthy volunteers, only zonisamide was detected in plasma. Zonisamide is excreted primarily in urine as parent drug and as the glucuronide of a metabolite. Following multiple dosing, 62% of the 14C dose was recovered in the urine, with 3% in the feces by day 10. Zonisamide undergoes acetylation to form N-acetyl zonisamide and reduction to form the open ring metabolite, 2–sulfamoylacetyl phenol (SMAP). Of the excreted dose, 35% was recovered as zonisamide, 15% as N-acetyl zonisamide, and 50% as the glucuronide of SMAP. Reduction of zonisamide to SMAP is mediated by cytochrome P450 isozyme 3A4 (CYP3A4). Zonisamide does not induce its own metabolism. Plasma clearance of zonisamide is approximately 0.30–0.35 mL/min/kg in patients not receiving enzyme-inducing antiepilepsy drugs (AEDs). The clearance of zonisamide is increased to 0.5 mL/min/kg in patients concurrently on enzyme-inducing AEDs.

Renal clearance is about 3.5 mL/min. The clearance of an oral dose of zonisamide from RBC is 2 mL/min.

Special Populations:

Renal Insufficiency:

Single 300 mg zonisamide doses were administered to three groups of volunteers. Group 1 was a healthy group with a creatinine clearance ranging from 70–152 mL/min. Group 2 and Group 3 had creatinine clearances ranging from 14.5–59 mL/min and 10–20 mL/min, respectively. Zonisamide renal clearance decreased with decreasing renal function (3.42, 2.50, 2.23 mL/min, respectively).

Marked renal impairment (creatinine clearance < 20 mL/min) was associated with an increase in zonisamide AUC of 35% (see DOSAGE AND ADMINISTRATIONsection).

Hepatic Disease:

The pharmacokinetics of zonisamide in patients with impaired liver function have not been studied (see DOSAGE AND ADMINISTRATION section).

Age:

The pharmacokinetics of a 300 mg single dose of zonisamide was similar in young (mean age 28 years) and elderly subjects (mean age 69 years).

Gender and Race:

Information on the effect of gender and race on the pharmacokinetics of zonisamide is not available.

Interactions of Zonisamide with Other Antiepilepsy Drugs (AEDs):

Concurrent medication with drugs that either induce or inhibit CYP3A4 may alter serum concentrations of zonisamide. Concomitant administration of phenytoin and carbamazepine increases zonisamide plasma clearance from 0.30-0.35 mL/min/kg to 0.35–0.5 mL/min/kg. The half-life of zonisamide is decreased to 27 hours by phenytoin, to 38 hours by phenobarbital and carbamazepine, and to 46 hours by valproate. Plasma protein binding of phenytoin and carbamazepine was not affected by zonisamide administration (see PRECAUTIONS, Drug Interactions subsection).

Interactions of Zonisamide with Other Carbonic Anhydrase Inhibitors:

Concomitant use of zonisamide, a carbonic anhydrase inhibitor, with any other carbonic anhydrase inhibitor (e.g., topiramate, acetazolamide or dichlorphenamide), may increase the severity of metabolic acidosis and may also increase the risk of kidney stone formation. Therefore, if zonisamide is given concomitantly with another carbonic anyhydrase inhibitor, the patient should be monitored for the appearance or worsening of metabolic acidosis (see PRECAUTIONS, Drug Interactions subsection).

Clinical Studies:

The effectiveness of zonisamide as adjunctive therapy (added to other antiepilepsy drugs) has been established in three multicenter, placebo-controlled, double blind, 3-month clinical trials (two domestic, one European) in 499 patients with refractory partial onset seizures with or without secondary generalization. Each patient had a history of at least four partial onset seizures per month in spite of receiving one or two antiepilepsy drugs at therapeutic concentrations. The 499 patients (209 women, 290 men) ranged in age from 13–68 years with a mean age of about 35 years. In the two US studies, over 80% of patients were Caucasian; 100% of patients in the European study were Caucasian.

Zonisamide or placebo was added to the existing therapy. The primary measure of effectiveness was median percent reduction from baseline in partial seizure frequency. The secondary measure was proportion of patients achieving a 50% or greater seizure reduction from baseline (responders). The results described below are for all partial seizures in the intent-to-treat populations.

In the first study (n = 203), all patients had a 1-month baseline observation period, then received placebo or zonisamide in one of two dose escalation regimens; either 1) 100 mg/day for five weeks, 200 mg/day for one week, 300 mg/day for one week, and then 400 mg/day for five weeks; or 2) 100 mg/day for one week, followed by 200 mg/day for five weeks, then 300 mg/day for one week, then 400 mg/day for five weeks. This design allowed a 100 mg vs. placebo comparison over weeks 1–5, and a 200 mg vs. placebo comparison over weeks 2–6; the primary comparison was 400 mg (both escalation groups combined) vs. placebo over weeks 8–12. The total daily dose was given as twice a day dosing. Statistically significant treatment differences favoring zonisamide were seen for doses of 100, 200, and 400 mg/day.

In the second (n = 152) and third (n = 138) studies, patients had a 2–3 month baseline, then were randomly assigned to placebo or zonisamide for three months. Zonisamide was introduced by administering 100 mg/day for the first week, 200 mg/day the second week, then 400 mg/day for two weeks, after which the dose (zonisamide or placebo) could be adjusted as necessary to a maximum dose of 20 mg/kg/day or a maximum plasma level of 40 mcg/mL. In the second study, the total daily dose was given as twice a day dosing; in the third study, it was given as a single daily dose. The average final maintenance doses received in the studies were 530 and 430 mg/day in the second and third studies, respectively. Both studies demonstrated statistically significant differences favoring zonisamide for doses of 400 to 600 mg/day, and there was no apparent difference between once daily and twice daily dosing (in different studies). Analysis of the data (first 4 weeks) during titration demonstrated statistically significant differences favoring zonisamide at doses between 100 and 400 mg/day. The primary comparison in both trials was for any dose over Weeks 5 – 12.

Table 1. Median % Reduction in All Partial Seizures and % Responders in Primary Efficacy Analyses: Intent-To-Treat Analysis

* p < 0.05 compared to placebo
Study	Median % reduction in partial seizures		% Responders
	Zonisamide	Placebo	Zonisamide	Placebo
Study 1:	n=98	n=72	n=98	n=72
Weeks 8-12:	40.5%*	9%	41.8%*	22.2%
Study 2:	n=69	n=72	n=69	n=72
Weeks 5-12:	29.6%*	-3.2%	29%	15%
Study 3:	n=67	n=66	n=67	n=66
Weeks 5-12:	27.2%*	-1.1%	28%*	12%

Table 2. Median % Reduction in All Partial Seizures and % Responders for Dose Analyses in Study 1: Intent-To-Treat Analysis

* p < 0.05 compared to placebo
Dose Group	Median % reduction in partial seizures		% Responders
	Zonisamide	Placebo	Zonisamide	Placebo
100-400 mg/day:	n=112	n=83	n=112	n=83
Weeks 1-12:	32.3%*	5.6%	32.1%*	9.6%
100 mg/day:	n=56	n=80	n=56	n=80
Weeks 1-5:	24.7%*	8.3%	25%*	11.3%
200 mg/day:	n=55	n=82	n=55	n=82
Weeks 2-6:	20.4%*	4%	25.5%*	9.8%

Figure 1 presents the proportion of patients (X-axis) whose percentage reduction from baseline in the all partial seizure rate was at least as great as that indicated on the Y-axis in the second and third placebo-controlled trials. A positive value on the Y-axis indicates an improvement from baseline (i.e., a decrease in seizure rate), while a negative value indicates a worsening from baseline (i.e., an increase in seizure rate). Thus, in a display of this type, the curve for an effective treatment is shifted to the left of the curve for placebo. The proportion of patients achieving any particular level of reduction in seizure rate was consistently higher for the zonisamide groups compared to the placebo groups. For example, Figure 1 indicates that approximately 27% of patients treated with zonisamide experienced a 75% or greater reduction, compared to approximately 12% in the placebo groups.

Figure 1: Proportion of Patients Achieving Differing Levels of Seizure Reduction in Zonisamide and Placebo Groups in Studies 2 and 3

No differences in efficacy based on age, sex or race, as measured by a change in seizure frequency from baseline, were detected.

Indications and Usage for Zonisamide Capsules

Zonisamide Capsules USP are indicated as adjunctive therapy in the treatment of partial seizures in adults with epilepsy.

Contraindications

Zonisamide Capsules are contraindicated in patients who have demonstrated hypersensitivity to sulfonamides or zonisamide.

Warnings

Potentially Fatal Reactions to Sulfonamides: Fatalities have occurred, although rarely, as a result of severe reactions to sulfonamides (zonisamide is a sulfonamide) including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias. Such reactions may occur when a sulfonamide is readministered irrespective of the route of administration. If signs of hypersensitivity or other serious reactions occur, discontinue zonisamide immediately. Specific experience with sulfonamide-type adverse reaction to zonisamide is described below.

Serious Skin Reactions: Consideration should be given to discontinuing zonisamide in patients who develop an otherwise unexplained rash. If the drug is not discontinued, patients should be observed frequently. Seven deaths from severe rash [i.e. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)] were reported in the first 11 years of marketing in Japan. All of the patients were receiving other drugs in addition to zonisamide. In post-marketing experience from Japan, a total of 49 cases of SJS or TEN have been reported, a reporting rate of 46 per million patient-years of exposure. Although this rate is greater than background, it is probably an underestimate of the true incidence because of under-reporting. There were no confirmed cases of SJS or TEN in the US, European, or Japanese development programs.

In the US and European randomized controlled trials, 6 of 269 (2.2%) zonisamide patients discontinued treatment because of rash compared to none on placebo. Across all trials during the US and European development, rash that led to discontinuation of zonisamide was reported in 1.4% of patients (12 events per 1000 patient-years of exposure). During Japanese development, serious rash or rash that led to study drug discontinuation was reported in 2% of patients (27.8 events per 1000 patient years). Rash usually occurred early in treatment, with 85% reported within 16 weeks in the US and European studies and 90% reported within two weeks in the Japanese studies. There was no apparent relationship of dose to the occurrence of rash.

Serious Hematologic Events:

Two confirmed cases of aplastic anemia and one confirmed case of agranulocytosis were reported in the first 11 years of marketing in Japan, rates greater than generally accepted background rates. There were no cases of aplastic anemia and two confirmed cases of agranulocytosis in the US, European, or Japanese development programs. There is inadequate information to assess the relationship, if any, between dose and duration of treatment and these events.

Oligohidrosis and Hyperthermia in Pediatric Patients:

Oligohidrosis, sometimes resulting in heat stroke and hospitalization, is seen in association with zonisamide in pediatric patients.

During the pre-approval development program in Japan, one case of oligohidrosis was reported in 403 pediatric patients, an incidence of 1 case per 285 patient-years of exposure. While there were no cases reported in the US or European development programs, fewer than 100 pediatric patients participated in these trials.

In the first 11 years of marketing in Japan, 38 cases were reported, an estimated reporting rate of about 1 case per 10,000 patient-years of exposure. In the first year of marketing in the US, 2 cases were reported, an estimated reporting rate of about 12 cases per 10,000 patient-years of exposure. These rates are underestimates of the true incidence because of under-reporting. There has also been one report of heat stroke in an 18-year-old patient in the US.

Decreased sweating and an elevation in body temperature above normal characterized these cases. Many cases were reported after exposure to elevated environmental temperatures. Heat stroke, requiring hospitalization, was diagnosed in some cases. There have been no reported deaths.

Pediatric patients appear to be at an increased risk for zonisamide-associated oligohidrosis and hyperthermia. Patients, especially pediatric patients, treated with zonisamide should be monitored closely for evidence of decreased sweating and increased body temperature, especially in warm or hot weather. Caution should be used when zonisamide is prescribed with other drugs that predispose patients to heat-related disorders; these drugs include, but are not limited to, carbonic anhydrase inhibitors and drugs with anticholinergic activity.

The practitioner should be aware that the safety and effectiveness of zonisamide in pediatric patients have not been established, and that zonisamide is not approved for use in pediatric patients.

Suicidal Behavior and Ideation

Antiepileptic drugs (AEDs), including zonisamide, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with any AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior.

Pooled analyses of 199 placebo-controlled, clinical trials (mono- and adjunctive therapy) of 11 different AEDs showed that patients randomized to one of the AEDs had approximately twice the risk (adjusted Relative Risk 1.8, 95% CI: 1.2, 2.7) of suicidal thinking or behavior compared to patients randomized to placebo. In these trials, which had a median treatment duration of 12 weeks, the estimated incidence rate of suicidal behavior or ideation among 27,863 AED-treated patients was 0.43%, compared to 0.24% among 16,029 placebo-treated patients, representing an increase of approximately one case of suicidal thinking or behavior for every 530 patients treated. There were four suicides in drug-treated patients in the trials and none in placebo-treated patients, but the number is too small to allow any conclusion about drug effect on suicide.

The increased risk of suicidal thoughts or behavior with AEDs was observed as early as one week after starting drug treatment with AEDs and persisted for the duration of treatment assessed. Because most trials included in the analysis did not extend beyond 24 weeks, the risk of suicidal thoughts or behavior beyond 24 weeks could not be assessed.

The risk of suicidal thoughts or behavior was generally consistent among drugs in the data analyzed. The finding of increased risk with AEDs of varying mechanisms of action and across a range of indications suggests that the risk applies to all AEDs used for any indication. The risk did not vary substantially by age (5-100 years) in the clinical trials analyzed.

Table 3 shows absolute and relative risk by indication for all evaluated AEDs.

Table 3: Risk by indication for antiepileptic drugs in the pooled analysis

Indication	Placebo Patients with Events per 1000 Patients	Drug Patients with Events per 1000 Patients	Relative Risk: Incidence of Events in Drug Patients/Incidence in Placebo Patients	Risk Difference: Additional Drug Patients with Events per 1000 Patients
Epilepsy	1	3.4	3.5	2.4
Psychiatric	5.7	8.5	1.5	2.9
Other	1	1.8	1.9	0.9
Total	2.4	4.3	1.8	1.9

The relative risk for suicidal thoughts or behavior was higher in clinical trials for epilepsy than in clinical trials for psychiatric or other conditions, but the absolute risk differences were similar for the epilepsy and psychiatric indications.

Anyone considering prescribing zonisamide or any other AED must balance the risk of suicidal thoughts or behavior with the risk of untreated illness. Epilepsy and many other illnesses for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Should suicidal thoughts and behavior emerge during treatment, the prescriber needs to consider whether the emergence of these symptoms in any given patient may be related to the illness being treated.

Patients, their caregivers, and families should be informed that AEDs increase the risk of suicidal thoughts and behavior and should be advised of the need to be alert for the emergence or worsening of the signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thought, behavior, or thoughts about self-harm. Behaviors of concern should be reported immediately to healthcare providers (see WARNINGS, Cognitive/ Neuropsychiatric Adverse Events subsection below).

Metabolic Acidosis:

Zonisamide causes hyperchloremic, non-anion gap, metabolic acidosis (i.e., decreased serum bicarbonate below the normal reference range in the absence of chronic respiratory alkalosis) (see PRECAUTIONS, Laboratory tests subsection). This metabolic acidosis is caused by renal bicarbonate loss due to the inhibitory effect of zonisamide on carbonic anhydrase.

Generally, zonisamide-induced metabolic acidosis occurs early in treatment, but it can develop at any time during treatment. Metabolic acidosis generally appears to be dose-dependent and can occur at doses as low as 25 mg daily.

Conditions or therapies that predispose to acidosis (such as renal disease, severe respiratory disorders, status epilepticus, diarrhea, ketogenic diet, or specific drugs) may be additive to the bicarbonate lowering effects of zonisamide.

Some manifestations of acute or chronic metabolic acidosis include hyperventilation, nonspecific symptoms such as fatigue and anorexia, or more severe sequelae including cardiac arrhythmias or stupor. Chronic, untreated, metabolic acidosis may increase the risk for nephrolithiasis or nephrocalcinosis. Nephrolithiasis has been observed in the clinical development program in 4% of adults treated with zonisamide, has also been detected by renal ultrasound in 8% of pediatric treated patients who had at least one ultrasound prospectively collected, and was reported as an adverse event in 3% (4/133) of pediatric patients (see PRECAUTIONS, Kidney Stones subsection).

Chronic, untreated metabolic acidosis may result in osteomalacia (referred to as rickets in pediatric patients) and/or osteoporosis with an increased risk for fracture. Of potential relevance, zonisamide treatment was associated with reductions in serum phosphorus and increases in serum alkaline phosphatase, changes that may be related to metabolic acidosis and osteomalacia (see PRECAUTIONS, Laboratory Tests subsection).

Chronic, untreated metabolic acidosis in pediatric patients may reduce growth rates. A reduction in growth rate may eventually decrease the maximal height achieved. The effect of zonisamide on growth and bone-related sequelae has not been systematically investigated.

Measurement of baseline and periodic serum bicarbonate during treatment is recommended. If metabolic acidosis develops and persists, consideration should be given to reducing the dose or discontinuing zonisamide (using dose tapering). If the decision is made to continue patients on zonisamide in the face of persistent acidosis, alkali treatment should be considered.

Serum bicarbonate was not measured in the adjunctive controlled trials of adults with epilepsy. However, serum bicarbonate was studied in three clinical trials for indications which have not been approved: a placebo-controlled trial for migraine prophylaxis in adults, a controlled trial for monotherapy in epilepsy in adults, and an open label trial for adjunctive treatment of epilepsy in pediatric patients (3-16 years). In adults, mean serum bicarbonate reductions ranged from approximately 2 mEq/L at daily doses of 100 mg to nearly 4mEq at daily doses of 300 mg. In pediatric patients, mean serum bicarbonate reductions ranged from approximately 2 mEq/L at daily doses from above 100mg up to 300 mg, to nearly 4 mEq/L at daily doses from above 400 mg up to 600 mg.

In two controlled studies in adults, the incidence of a persistent treatment-emergent decrease in serum bicarbonate to less than 20 mEq/L (observed at 2 or more consecutive visits or the final visit) was dose-related at relatively low zonisamide doses. In the monotherapy trial of epilepsy, the incidence of a persistent treatment-emergent decrease in serum bicarbonate was 21% for daily zonisamide doses of 25 mg or 100 mg, and was 43% at a daily dose of 300 mg. In a placebo-controlled trial for prophylaxis of migraine, the incidence of a persistent treatment-emergent decrease in serum bicarbonate was 7% for placebo, 29% for 150mg daily, and 34% for 300mg daily. The incidence of persistent markedly abnormally low serum bicarbonate (decrease to less than 17 mEq/L and more than 5 mEq/L from a pretreatment value of at least 20 mEq/L in these controlled trials was 2% or less.

In the pediatric study, the incidence of persistent, treatment-emergent decreases in serum bicarbonate to levels less than 20 mEq/L was 52%at doses up to 100 mg daily, was 90% for a wide range of doses up to 600 mg daily, and generally appeared to increase with higher doses. The incidence of a persistent markedly abnormally low serum bicarbonate value was 4% at doses up to 100 mg daily, was 18% for a wide range of doses up to 600 mg daily, and generally appeared to increase with higher doses. Some patients experienced moderately severe serum bicarbonate decrements down to a level as low as 10 mEq/L.

The relatively high frequencies of varying severities of metabolic acidosis observed in this study of pediatric patients (compared to the frequency and severity observed in various clinical trial development programs in adults) suggest that pediatric patients may be more likely to develop metabolic acidosis than adults.

Seizures on Withdrawal:

As with other AEDs, abrupt withdrawal of zonisamide in patients with epilepsy may precipitate increased seizure frequency or status epilepticus. Dose reduction or discontinuation of zonisamide should be done gradually.

Teratogenicity:

Women of child bearing potential who are given zonisamide should be advised to use effective contraception. Zonisamide was teratogenic in mice, rats, and dogs and embryolethal in monkeys when administered during the period of organogenesis. A variety of fetal abnormalities, including cardiovascular defects, and embryo-fetal deaths occurred at maternal plasma levels similar to or lower than therapeutic levels in humans. These findings suggest that the use of zonisamide during pregnancy in humans may present a significant risk to the fetus (see PRECAUTIONS, Pregnancy subsection).

Zonisamide should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Cognitive/ Neuropsychiatric Adverse Events:

Use of zonisamide was frequently associated with central nervous system-related adverse events. The most significant of these can be classified into three general categories: 1) psychiatric symptoms, including depression and psychosis, 2) psychomotor slowing, difficulty with concentration, and speech or language problems, in particular, word-finding difficulties, and 3) somnolence or fatigue.

In placebo-controlled trials, 2.2% of patients discontinued zonisamide or were hospitalized for depression compared to 0.4% of placebo patients. Among all epilepsy patients treated with zonisamide, 1.4% were discontinued and 1% were hospitalized because of reported depression or suicide attempts. In placebo-controlled trials, 2.2% of patients discontinued zonisamide or were hospitalized due to psychosis or psychosis-related symptoms compared to none of the placebo patients. Among all epilepsy patients treated with zonisamide, 0.9% were discontinued and 1.4% were hospitalized because of reported psychosis or related symptoms.

Psychomotor slowing and difficulty with concentration occurred in the first month of treatment and were associated with doses above 300 mg/day. Speech and language problems tended to occur after 6–10 weeks of treatment and at doses above 300 mg/day. Although in most cases these events were of mild to moderate severity, they at times led to withdrawal from treatment.

Somnolence and fatigue were frequently reported CNS adverse events during clinical trials with zonisamide. Although in most cases these events were of mild to moderate severity, they led to withdrawal from treatment in 0.2% of the patients enrolled in controlled trials. Somnolence and fatigue tended to occur within the first month of treatment. Somnolence and fatigue occurred most frequently at doses of 300–500 mg/day. Patients should be cautioned about this possibility and special care should be taken by patients if they drive, operate machinery, or perform any hazardous task.

Precautions

General

Somnolence is commonly reported, especially at higher doses of zonisamide (see WARNINGS: Cognitive/ Neuropsychiatric Adverse Eventssubsection). Zonisamide is metabolized by the liver and eliminated by the kidneys; caution should therefore be exercised when administering zonisamide to patients with hepatic and renal dysfunction (see CLINICAL PHARMACOLOGY, Special Populations subsection).

Kidney Stones:

Among 991 patients treated during the development of zonisamide, 40 patients (4%) with epilepsy receiving zonisamide developed clinically possible or confirmed kidney stones (e.g. clinical symptomatology, sonography, etc.), a rate of 34 per 1000 patient-years of exposure (40 patients with 1168 years of exposure). Of these, 12 were symptomatic, and 28 were described as possible kidney stones based on sonographic detection. In nine patients, the diagnosis was confirmed by a passage of a stone or by a definitive sonographic finding. The rate of occurrence of kidney stones was 28.7 per 1000 patient-years of exposure in the first six months, 62.6 per 1000 patient-years of exposure between 6 and 12 months, and 24.3 per 1000 patient-years of exposure after 12 months of use. There are no normative sonographic data available for either the general population or patients with epilepsy.

Although the clinical significance of the sonographic findings may not be certain, the development of nephrolithiasis may be related to metabolic acidosis (see WARNINGS, Metabolic Acidosis subsection). The analyzed stones were composed of calcium or urate salts. In general, increasing fluid intake and urine output can help reduce the risk of stone formation, particularly in those with predisposing risk factors. It is unknown, however, whether these measures will reduce the risk of stone formation in patients treated with zonisamide.

Although not approved in pediatric patients, sonographic findings consistent with nephrolithiasis were also detected in 8% of a subset of zonisamide treated pediatric patients who had at least one renal ultrasound prospectively performed in a clinical development development program investigating open-label treatment. The incidence of kidney stone as an adverse event was 3% (see WARNINGS, Metabolic Acidosis subsection).

Effect on Renal Function:

In several clinical studies, zonisamide was associated with a statistically significant 8% mean increase from baseline of serum creatinine and blood urea nitrogen (BUN) compared to essentially no change in the placebo patients. The increase appeared to persist over time but was not progressive; this has been interpreted as an effect on glomerular filtration rate (GFR). There were no episodes of unexplained acute renal failure in clinical development in the US, Europe, or Japan. The decrease in GFR appeared within the first 4 weeks of treatment. In a 30-day study, the GFR returned to baseline within 2–3 weeks of drug discontinuation. There is no information about reversibility, after drug discontinuation, of the effects on GFR after long-term use. Zonisamide should be discontinued in patients who develop acute renal failure or a clinically significant sustained increase in the creatinine/BUN concentration. Zonisamide should not be used in patients with renal failure (estimated GFR < 50 mL/min) as there has been insufficient experience concerning drug dosing and toxicity.

Sudden Unexplained Death in Epilepsy:

During the development of zonisamide, nine sudden unexplained deaths occurred among 991 patients with epilepsy receiving zonisamide for whom accurate exposure data are available. This represents an incidence of 7.7 deaths per 1000 patient years. Although this rate exceeds that expected in a healthy population, it is within the range of estimates for the incidence of sudden unexplained deaths in patients with refractory epilepsy not receiving zonisamide (ranging from 0.5 per 1000 patient-years for the general population of patients with epilepsy, to 2–5 per 1000 patient-years for patients with refractory epilepsy; higher incidences range from 9–15 per 1000 patient-years among surgical candidates and surgical failures). Some of the deaths could represent seizure-related deaths in which the seizure was not observed.

Status Epilepticus:

Estimates of the incidence of treatment emergent status epilepticus in zonisamide-treated patients are difficult because a standard definition was not employed. Nonetheless, in controlled trials, 1.1% of patients treated with zonisamide had an event labeled as status epilepticus compared to none of the patients treated with placebo. Among patients treated with zonisamide across all epilepsy studies (controlled and uncontrolled), 1% of patients had an event reported as status epilepticus.

Information for Patients

Patients should be informed of the availability of a Medication Guide, and they should be instructed to read the Medication Guide prior to taking zonisamide. Patients should be instructed to take zonisamide only as prescribed.

Patients should be advised as follows: (See Medication Guide)

1. Zonisamide may produce drowsiness, especially at higher doses. Patients should be advised not to drive a car or operate other complex machinery until they have gained experience on zonisamide sufficient to determine whether it affects their performance. Because of the potential of zonisamide to cause CNS depression, as well as other cognitive and/or neuropsychiatric adverse events, zonisamide should be used with caution if used in combination with alcohol or other CNS depressants.


2. Patients should contact their physician immediately if a skin rash develops or seizures worsen.


3. Patients should contact their physician immediately if they develop signs or symptoms, such as sudden back pain, abdominal pain, and/or blood in the urine, that could indicate a kidney stone. Increasing fluid intake and urine output may reduce the risk of stone formation, particularly in those with predisposing risk factors for stones.


4. Patients should contact their physician immediately if a child has been taking zonisamide and is not sweating as usual with or without a fever.


5. Because zonisamide can cause hematological complications, patients should contact their physician immediately if they develop a fever, sore throat, oral ulcers, or easy bruising.


6. Suicidal Thinking and Behavior – Patients, their caregivers, and families should be counseled that AEDs, including zonisamide, may increase the risk of suicidal thoughts and behavior and should be advised of the need to be alert for the emergence or worsening of symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts, behavior, or thoughts about self-harm. Behaviors of concern should be reported immediat

All-Nite

Generic Name: acetaminophen, dextromethorphan, and doxylamine (a SEET a MIN oh fen, DEX tro me THOR fan, and dox IL a meen)

Brand Names: All-Nite, Coricidin HBP Nighttime Multi-Symptom Cold, Cough & Sore Throat Nighttime, Delsym Nighttime Cough & Cold, Multi-Symptom Nighttime Cold & Flu Relief, Multi-Symptom Nighttime Cold & Flu Relief (cherry), Night Time Cold/Flu, Nite Time Cold & Flu, Nite Time Cold & Flu Relief, Nyquil Cold & Flu, NyQuil Cold/Flu Relief, NyQuil Cold/Flu Relief Cherry, Tylenol Cold & Cough Nighttime Cool Burst, Tylenol Cough & Sore Throat Night Time, Tylenol Warming Cough & Sore Throat Nightime

What is All-Nite (acetaminophen, dextromethorphan, and doxylamine)?

Acetaminophen is a pain reliever and fever reducer.

Doxylamine is an antihistamine that reduces the effects of the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Dextromethorphan is a cough suppressant. It affects the cough reflex in the brain that triggers coughing.

The combination of acetaminophen, doxylamine, and dextromethorphan is used to treat headache, fever, body aches, cough, runny nose, sneezing, itching, and watery eyes caused by allergies, the common cold, or the flu.

This medicine will not treat a cough that is caused by smoking, asthma, or emphysema.

Acetaminophen, doxylamine, and dextromethorphan may also be used for purposes not listed in this medication guide.

What is the most important information I should know about this medicine?

Do not take more of this medication than is recommended. An overdose of acetaminophen can damage your liver or cause death. Do not take this medication without a doctor's advice if you have ever had alcoholic liver disease (cirrhosis) or if you drink more than 3 alcoholic beverages per day. You should not use this medicine if you have severe constipation, a blockage in your stomach or intestines, or if you are unable to urinate. Do not use this medicine if you have untreated or uncontrolled diseases such as glaucoma, asthma or COPD, high blood pressure, heart disease, coronary artery disease, or overactive thyroid. Do not use this medicine if you have used an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects. Avoid drinking alcohol. It may increase your risk of liver damage while you are taking acetaminophen, and can increase certain side effects of doxylamine. Ask a doctor or pharmacist before using any other cold, allergy, pain, or sleep medication. Acetaminophen (sometimes abbreviated as APAP) is contained in many combination medicines. Taking certain products together can cause you to get too much acetaminophen which can lead to a fatal overdose. Check the label to see if a medicine contains acetaminophen or APAP.

What should I discuss with my healthcare provider before taking this medicine?

You should not use this medicine if you have severe constipation, a blockage in your stomach or intestines, or if you are unable to urinate. Do not use this medicine if you have untreated or uncontrolled diseases such as glaucoma, asthma or COPD, high blood pressure, heart disease, coronary artery disease, or overactive thyroid. Do not use this medicine if you have used an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have:

• 
  

  liver disease, cirrhosis, a history of alcoholism, or if you drink more than 3 alcoholic beverages per day;

  
  


• 
  

  a blockage in your digestive tract (stomach or intestines);

  
  


• 
  

  kidney disease;

  
  


• 
  

  cough with mucus, or cough caused by emphysema or chronic bronchitis;

  
  


• 
  

  enlarged prostate or urination problems; or

  
  


• 
  

  if you take potassium (Cytra, Epiklor, K-Lyte, K-Phos, Kaon, Klor-Con, Polycitra, Urocit-K).

  
  

It is not known whether acetaminophen, doxylamine, and dextromethorphan will harm an unborn baby. Do not use this medicine without a doctor's advice if you are pregnant. Acetaminophen, doxylamine, and dextromethorphan may pass into breast milk and may harm a nursing baby. Antihistamines may also slow breast milk production. Do not use this medicine without a doctor's advice if you are breast-feeding a baby.

Artificially sweetened cold medicine may contain phenylalanine. If you have phenylketonuria (PKU), check the medication label to see if the product contains phenylalanine.

How should I take this medicine?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. This medicine is usually taken only for a short time until your symptoms clear up.

Do not take more of this medication than is recommended. An overdose of acetaminophen can damage your liver or cause death. Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Measure liquid medicine with a special dose measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose measuring device, ask your pharmacist for one.

Do not take for longer than 7 days in a row. Stop taking the medicine and call your doctor if you still have a fever after 3 days of use, you still have pain after 7 days (or 5 days if treating a child), if your symptoms get worse, or if you have a skin rash, ongoing headache, or any redness or swelling.

If you need surgery or medical tests, tell the surgeon or doctor ahead of time if you have taken this medicine within the past few days. Store at room temperature away from moisture and heat. Do not allow liquid medicine to freeze.

What happens if I miss a dose?

Since this medicine is taken when needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of acetaminophen can be fatal.

The first signs of an acetaminophen overdose include loss of appetite, nausea, vomiting, stomach pain, sweating, and confusion or weakness. Later symptoms may include pain in your upper stomach, dark urine, and yellowing of your skin or the whites of your eyes.

Overdose symptoms may also include severe forms of some of the side effects listed in this medication guide.

What should I avoid while taking this medicine?

Ask a doctor or pharmacist before using any other cold, allergy, pain, or sleep medication. Acetaminophen (sometimes abbreviated as APAP) is contained in many combination medicines. Taking certain products together can cause you to get too much acetaminophen which can lead to a fatal overdose. Check the label to see if a medicine contains acetaminophen or APAP. Avoid drinking alcohol. It may increase your risk of liver damage while you are taking acetaminophen, and can increase certain side effects of doxylamine. This medicine may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

This medicine side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat. Stop using this medication and call your doctor at once if you have a serious side effect such as:

• 
  

  chest pain, rapid pulse;

  
  


• 
  

  fast, slow, or uneven heart rate;

  
  


• 
  

  severe dizziness or anxiety, feeling like you might pass out;

  
  


• 
  

  severe headache;

  
  


• 
  

  mood changes, confusion, hallucinations, severe nervousness;

  
  


• 
  

  tremor, seizure (convulsions);

  
  


• 
  

  fever, easy bruising or bleeding, unusual weakness;

  
  


• 
  

  urinating less than usual or not at all;

  
  


• 
  

  nausea, pain in your upper stomach, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of your skin or eyes); or

  
  


• 
  

  dangerously high blood pressure (severe headache, blurred vision, buzzing in your ears, anxiety, chest pain, uneven heartbeats, seizure).

  
  

Less serious side effects may include:

• 
  

  dizziness, drowsiness, mild headache;

  
  


• 
  

  dry mouth, nose, or throat;

  
  


• 
  

  constipation, diarrhea, mild nausea, upset stomach;

  
  


• 
  

  blurred vision;

  
  


• 
  

  feeling restless or irritable; or

  
  


• 
  

  sleep problems (insomnia).

  
  

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect this medicine?

Ask a doctor or pharmacist before using this medicine if you regularly use other medicines that make you sleepy (such as narcotic pain medication, sedatives, sleeping pills, muscle relaxers, and medicine for seizures, depression or anxiety). They can add to sleepiness caused by doxylamine.

Ask a doctor or pharmacist if it is safe for you to use acetaminophen, doxylamine, and dextromethorphan if you are also using any of the following drugs:

• 
  

  leflunomide (Arava);

  
  


• 
  

  topiramate (Topamax);

  
  


• 
  

  zonisamide (Zonegran);

  
  


• 
  

  an antibiotic, antifungal medicine, sulfa drug, or tuberculosis medicine;

  
  


• 
  

  an antidepressant;

  
  


• 
  

  birth control pills or hormone replacement therapy;

  
  


• 
  

  bladder or urinary medications;

  
  


• 
  

  blood pressure medication;

  
  


• 
  

  a bronchodilator;

  
  


• 
  

  cancer medicine;

  
  


• 
  

  cholesterol-lowering medications such as Lipitor, Niaspan, Zocor, Vytorin, and others;

  
  


• 
  

  gout or arthritis medications (including gold injections);

  
  


• 
  

  HIV/AIDS medication;

  
  


• 
  

  medication for nausea and vomiting, stomach ulcers, or irritable bowel syndrome;

  
  


• 
  

  medicines to treat psychiatric disorders;

  
  


• 
  

  an NSAID such as Advil, Aleve, Arthrotec, Cataflam, Celebrex, Indocin, Motrin, Naprosyn, Treximet, Voltaren, others; or

  
  


• 
  

  seizure medication.

  
  

This list is not complete and there may be other drugs that can affect acetaminophen, dextromethorphan, and doxylamine. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

More All-Nite resources

• All-Nite Side Effects (in more detail)
• All-Nite Use in Pregnancy & Breastfeeding
• All-Nite Drug Interactions
• All-Nite Support Group
• 0 Reviews for All-Nite - Add your own review/rating

Compare All-Nite with other medications

• Cough
• Pain

Where can I get more information?

• Your pharmacist can provide more information about acetaminophen, dextromethorphan, and doxylamine.

See also: All-Nite side effects (in more detail)

Zyflo CR

Generic Name: zileuton (Oral route)

zye-LOO-ton

Commonly used brand name(s)

In the U.S.

• Zyflo


• Zyflo CR

Available Dosage Forms:

• Tablet


• Tablet, Extended Release

Therapeutic Class: Anti-Inflammatory

Pharmacologic Class: Leukotriene Pathway Inhibitor

Uses For Zyflo CR

Zileuton is used by patients with mild-to-moderate chronic asthma to decrease the symptoms of asthma and the number of acute asthma attacks. However, this medicine should not be taken to relieve an asthma attack that has already started.

This medicine is available only with your doctor's prescription.

Zileuton immediate-release tablets (Zyflo(R)) were withdrawn from the U. S. market by Critical Therapeutics on February 12, 2008. The extended-release formulation of zileuton (Zyflo CR(R)), also manufactured by Critical Therapeutics, Inc, is still available.

Before Using Zyflo CR

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of zileuton in children younger than 12 years of age. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of zileuton in the elderly. However, elderly patients are more likely to have age-related liver disease, and this medicine should not be used in patients with this condition.

Pregnancy

	Pregnancy Category	Explanation
All Trimesters	C	Animal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Astemizole


• Eltrombopag


• Pimozide


• Terfenadine


• Theophylline


• Tizanidine

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Propranolol


• Warfarin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Alcohol use, severe or


• Liver disease, history of—Use with caution. The chance of serious side effects may be increased.

• Liver disease, active—This medicine should not be used with this condition.

Proper Use of zileuton

This section provides information on the proper use of a number of products that contain zileuton. It may not be specific to Zyflo CR. Please read with care.

Zileuton is used to prevent asthma attacks. It is not used to relieve an attack that has already started. For relief of an asthma attack that has already started, you should use another inhaled medicine that works quickly. If you have any questions about this, check with your doctor.

Swallow the extended-release tablet whole. Do not crush, break, or chew it.

To work properly, zileuton must be taken every day at regularly spaced times, even if your asthma seems better.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (extended-release tablets):
  
  • For asthma prevention:
    
    • Adults and children 12 years of age and older—Two 600 milligram (mg) tablets two times a day, within one hour after morning and evening meals.
    
    
    • Children up to 12 years of age—Use and dose must be determined by your doctor.
    
    
  
  

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions While Using Zyflo CR

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to check for unwanted effects.

Check with your doctor if you are using more inhalations (puffs) than usual of your inhaled bronchodilator to relieve an acute asthma attack.

You may be taking other medicines for asthma along with zileuton. Do not stop taking or reduce the dose of the other medicines, even if your asthma seems better, unless you are told to do so by your doctor.

You should limit the amount of alcohol you drink while you are taking this medicine.

This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed and have problems with sleep. If you or your caregiver notice any of these side effects, tell your doctor right away.

Zyflo CR Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Rare

• Flu-like symptoms


• itching


• right upper stomach pain


• unusual tiredness or weakness


• yellow eyes or skin

Incidence not known

• Attack, assault, or force


• attempts at killing oneself


• discouragement


• dry mouth


• fear or nervousness


• feeling sad or empty


• hyperventilation


• irregular heartbeats


• irritability


• lack of appetite


• loss of interest or pleasure


• restlessness


• seeing, hearing, or feeling things that are not there


• shakiness in the legs, arms, hands, or feet


• shortness of breath


• sleeplessness


• tiredness


• trembling or shaking of the hands or feet


• trouble with concentrating


• trouble with sleeping


• unable to sleep

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Cough


• fever


• headache


• nausea


• pain or tenderness around the eyes and cheekbones


• stuffy or runny nose


• tightness of the chest or wheezing


• troubled breathing


• upset stomach

Less common

• Abdominal or stomach pain


• sore throat


• weakness

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

See also: Zyflo CR side effects (in more detail)

The information contained in the Thomson Reuters Micromedex products as delivered by Drugs.com is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

The use of the Thomson Reuters Healthcare products is at your sole risk. These products are provided "AS IS" and "as available" for use, without warranties of any kind, either express or implied. Thomson Reuters Healthcare and Drugs.com make no representation or warranty as to the accuracy, reliability, timeliness, usefulness or completeness of any of the information contained in the products. Additionally, THOMSON REUTERS HEALTHCARE MAKES NO REPRESENTATION OR WARRANTIES AS TO THE OPINIONS OR OTHER SERVICE OR DATA YOU MAY ACCESS, DOWNLOAD OR USE AS A RESULT OF USE OF THE THOMSON REUTERS HEALTHCARE PRODUCTS. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR USE ARE HEREBY EXCLUDED. Thomson Reuters Healthcare does not assume any responsibility or risk for your use of the Thomson Reuters Healthcare products.

More Zyflo CR resources

• Zyflo CR Side Effects (in more detail)
• Zyflo CR Use in Pregnancy & Breastfeeding
• Zyflo CR Drug Interactions
• Zyflo CR Support Group
• 0 Reviews for Zyflo CR - Add your own review/rating

• Zyflo CR Prescribing Information (FDA)


• Zyflo CR Concise Consumer Information (Cerner Multum)


• Zyflo CR Extended-Release Tablets MedFacts Consumer Leaflet (Wolters Kluwer)


• Zileuton Monograph (AHFS DI)


• Zileuton Professional Patient Advice (Wolters Kluwer)


• Zileuton MedFacts Consumer Leaflet (Wolters Kluwer)


• Zyflo Prescribing Information (FDA)

Compare Zyflo CR with other medications

• Asthma, Maintenance