Zonisamide

Class: Anticonvulsants, Miscellaneous
VA Class: CN400
Chemical Name: 1,2-Benzisoxazole-3-methanesulfonamide
Molecular Formula: C₈H₈N₂O₃S
CAS Number: 68291-97-4
Brands: Zonegran

REMS:

FDA approved a REMS for zonisamide to ensure that the benefits of a drug outweigh the risks. However, FDA later rescinded REMS requirements. See the FDA REMS page () or the ASHP REMS Resource Center ().

Introduction

Anticonvulsant; a sulfonamide.^{1 2 3}

Uses for Zonisamide

Seizure Disorders

Management (in combination with other anticonvulsants) of partial seizures in adults with epilepsy.^{1 2 3 8}

Zonisamide Dosage and Administration

General

• 
  

  Zonisamide therapy should not be discontinued abruptly; dosage reduction or discontinuance of the drug should be done gradually.¹

  
  


• 
  

  Closely monitor for marked changes in behavior that could indicate emergence or worsening of suicidal thoughts or behavior or depression.^{1 14 15 16 21} (See Suicidality Risk under Cautions.)

  
  

Administration

Oral Administration

Administer orally without regard to meals.^{1 2 3} Patients should be encouraged to drink 6–8 glasses of water each day while receiving the drug.¹

Administer initial dosage (100 mg daily) once daily; following dosage adjustment, administer once or twice daily.^{1 2 3}

Swallow capsules whole.¹

Dosage

Adults

Seizure Disorders

Partial Seizures

Oral

Adults >16 years of age: Initially, 100 mg daily.^{1 2 3 9}

After 2 weeks, dosage may be increased to 200 mg daily.^{1 3} Dosage can be further increased to 300 and 400 mg daily;^{1 2 3 9} allow ≥2 weeks between dosage changes (to achieve steady state at each dosage level).^{1 2 3 9} Some clinicians may prefer to administer lower dosages for longer periods (in order to fully assess safety at steady state).¹

Dosages >400 mg daily may not be associated with increased therapeutic benefit.¹

Adverse effects occur more frequently at dosages ≥300 mg daily.¹

Prescribing Limits

Adults

Seizure Disorders

Partial Seizures

Oral

Limited experience with dosages >600 mg daily.¹

Special Populations

Hepatic Impairment

Titrate dosage slowly in patients with hepatic disease.¹

Renal Impairment

Titrate dosage slowly in patients with renal disease.^{1 2} Do not use in patients with renal failure (GFR <50 mL/minute).¹

Geriatric Patients

No specific dosage recommendations for zonisamide; however, select dosage cautiously, usually starting at the lower end of the dosage range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and of concomitant diseases or other drug therapy in this population.¹

Cautions for Zonisamide

Contraindications

• 
  

  Known hypersensitivity to zonisamide, sulfonamides, or any ingredient in the formulation.^{1 2}

  
  

Warnings/Precautions

Warnings

Hematologic Effects

Aplastic anemia and agranulocytosis reported rarely; causal relationship between these events and dosage or duration of therapy not established.^{1 2}

Oligohidrosis and Hyperthermia

Oligohidrosis (a reduction in sweating) and hyperthermia reported in patients receiving zonisamide, particularly in pediatric patients.^{1 13 26} Closely monitor patients receiving zonisamide for evidence of decreased sweating and increased body temperature, particularly in warm or hot weather.^{1 13 26} Consider risk of hyperthermia when zonisamide is used concomitantly with other drugs that predispose patients to heat-related disorders.^{1 13} (See Pediatric Use under Cautions, Drugs Predisposing to Heat-related Disorders under Interactions, and Advice to Patients.)

Suicidality Risk

Increased risk of suicidality (suicidal ideation or behavior) observed in an analysis of studies using various anticonvulsants, including zonisamide, in patients with epilepsy, psychiatric disorders (e.g., bipolar disorder, depression, anxiety), and other conditions (e.g., migraine, neuropathic pain); risk in patients receiving anticonvulsants (0.43%) was approximately twice that in patients receiving placebo (0.24%).^{1 14 15 16 21} Increased suicidality risk was observed ≥1 week after initiation of anticonvulsant therapy and continued through 24 weeks.^{14 15 16} Risk was higher for patients with epilepsy compared with those receiving anticonvulsants for other conditions.^{1 14 15 16}

Closely monitor all patients currently receiving or beginning anticonvulsant therapy for changes in behavior that may indicate emergence or worsening of suicidal thoughts or behavior or depression.^{1 14 15 16 21} Anxiety, agitation, hostility, hypomania, and mania may be precursors to emerging suicidality.¹⁵

Balance risk of suicidality with the risk of untreated illness.^{1 15} Epilepsy and other illnesses treated with anticonvulsants are themselves associated with morbidity and mortality and an increased risk of suicidality.^{1 21} If suicidal thoughts or behavior emerge during anticonvulsant therapy, consider whether these symptoms may be related to the illness itself.^{1 21} (See Advice to Patients.)

Metabolic Acidosis

Zonisamide can cause metabolic acidosis, characterized by hyperchloremia and decreased serum bicarbonate concentrations.¹⁹ Often asymptomatic, but signs and symptoms of persistent metabolic acidosis may include hyperventilation, fatigue, and anorexia; more severe symptoms may include cardiac arrhythmias and stupor.¹⁹ Generally occurs early in treatment, but may occur at any time during therapy.¹⁹

Risk of developing metabolic acidosis appears greater at higher dosages of zonisamide, but it can occur with dosages ≤25 mg daily.¹⁹ Renal disease, severe respiratory disorders, diarrhea, surgery, ketogenic diets, or other drugs (e.g., acetazolamide) may predispose patients to acidosis.¹⁹ Also appears to be more frequent and severe in younger patients.¹⁹ (See Pediatric Use under Cautions.)

Decreases in serum bicarbonate levels are usually mild to moderate (average decrease of approximately 2 mEq/L) in adults; however, some adults have experienced severe decreases (as much as 10 mEq/L below their baseline).¹⁹ Chronic, untreated metabolic acidosis may increase the risk for renal calculi (kidney stones), nephrocalcinosis, and bone abnormalities (e.g., osteoporosis, osteomalacia, rickets in children) with an increased risk of fractures.¹⁹ (See Renal Calculi under Cautions.)

FDA recommends that clinicians measure serum bicarbonate levels prior to and periodically during zonisamide therapy, even in the absence of clinical symptoms, as well as if signs or symptoms of metabolic acidosis are observed.¹⁹ If metabolic acidosis develops and persists, consider reducing the zonisamide dosage or discontinuing the drug (by slowly reducing the dosage) and modifying the patient’s anticonvulsant drug regimen as appropriate.¹⁹ If the decision is made to continue patients with metabolic acidosis on zonisamide, consider alkali treatment.¹⁹

Withdrawal Seizures

Abrupt withdrawal may result in increased seizure frequency or status epilepticus; withdraw zonisamide gradually and reduce dosage slowly.¹

Cognitive/Neuropsychiatric Effects

Possible somnolence or fatigue, psychiatric symptoms (e.g., depression, psychosis), and impaired psychomotor or cognitive performance (e.g., difficulties in concentrating, language, speech, and word finding).^{1 3 5 15 17} (See Suicidality Risk under Cautions.)

Status Epilepticus

In controlled studies, status epilepticus occurred in 1.1 or 0% of patients receiving zonisamide or placebo, respectively.¹ In all (uncontrolled and controlled) clinical studies of zonisamide therapy, the incidence of status epilepticus was 1%.¹

Sensitivity Reactions

Dermatologic and Sensitivity Reactions

Fatalities resulting from severe reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, have occurred following zonisamide use.^{1 2 7}

Fatalities resulting from fulminant hepatic necrosis, agranulocytosis, aplastic anemia, or other blood dyscrasias rarely have been caused by sulfonamides.^{1 2}

Discontinue immediately if signs or symptoms of hypersensitivity occur.¹ Consider drug discontinuance if unexplained rash occurs; if drug is not discontinued, observe patient frequently.¹

General Precautions

Renal Calculi

Clinically possible or confirmed renal calculi (kidney stones), composed of calcium or urate salts, reported.^{1 2 3 4 8 9 12}

In general, increasing fluid intake and urine output may reduce the risk of kidney stone formation, particularly in patients with predisposing risk factors; not known whether these measures reduce the risk of kidney stone formation in patients receiving zonisamide.¹

Other Renal Effects

Substantial increases in S_cr and BUN reported;¹ such increases appeared to persist over time but were not progressive.¹ Consider periodically monitoring renal function during zonisamide therapy.¹

Discontinue use in patients who develop acute renal failure or clinically important, sustained increases in S_cr and BUN.¹

Sudden, Unexplained Deaths in Epilepsy

Higher incidence of sudden and unexplained deaths than would be expected in a healthy (nonepileptic) population; however, incidence is within range of estimates for patients with refractory epilepsy.¹

Specific Populations

Pregnancy

Category C.¹

North American Antiepileptic Drug Pregnancy Registry at 888-233-2334 (for patients).¹

FDA warns that zonisamide may cause metabolic acidosis;¹⁹ if metabolic acidosis occurs during pregnancy, may affect fetal development (i.e., decreased fetal growth, decreased fetal oxygenation, and fetal death) and the ability of the fetus to tolerate labor.¹⁹

The effect of zonisamide on labor and delivery is unknown.¹

Physiologic changes during pregnancy may affect plasma zonisamide concentrations and/or therapeutic effect.¹ (See Special Populations under Pharmacokinetics: Elimination.) Some clinicians recommend closely monitoring zonisamide concentrations and adjusting zonisamide dosage as necessary in pregnant women.²⁰

Lactation

Distributes into human milk.^{18 19} Due to potential risk in nursing infant, discontinue nursing or the drug.¹

Pediatric Use

Safety and efficacy of zonisamide not established in children <16 years of age and the drug is not approved for use in pediatric patients in the US.^{1 19} However, the drug has been used in some pediatric patients† for the treatment of epilepsy to date and is approved for pediatric use in Japan.^{19 22 23 24 25 26 27}

Oligohidrosis and hyperthermia, characterized by decreased sweating and abnormally high body temperatures, reported in pediatric patients (1.6–17 years of age) receiving zonisamide and sometimes have resulted in heat stroke and hospitalization.^{1 2 3 11 13}

Closely monitor children receiving the drug for evidence of decreased sweating and increased body temperature, especially in warm or hot weather.^{1 13 26} Consider risk of hyperthermia when zonisamide is used concomitantly with other drugs that predispose patients to heat-related disorders.^{1 13} (See Oligohidrosis and Hyperthermia under Cautions, Drugs Predisposing to Heat-related Disorders under Interactions, and Advice to Patients.)

Pediatric patients may be at increased risk for zonisamide-induced metabolic acidosis; may be more severe in younger patients.¹⁹ Specific effects of zonisamide on growth and bone not studied; chronic metabolic acidosis may reduce growth rates in pediatric patients, resulting in a reduction in the maximal height achieved.¹⁹ (See Metabolic Acidosis under Cautions, Specific Drugs under Interactions, and Advice to Patients.)

Geriatric Use

Insufficient experience in patients ≥65 years of age to determine whether they respond differently than younger adults.¹

Hepatic Impairment

Use with caution in patients with hepatic disease; slower dosage titration and more frequent monitoring may be necessary.¹ (See Hepatic Impairment under Dosage and Administration.)

Renal Impairment

Use with caution in patients with renal disease; slower dosage titration and more frequent monitoring may be necessary.¹

Because of insufficient experience concerning dosage and toxicity, do not use in patients with renal failure (GFR <50 mL/minute).¹ (See Renal Impairment under Dosage and Administration.)

Common Adverse Effects

Abdominal pain, anorexia, diarrhea, nausea, dyspepsia, constipation, dry mouth, taste perversion, headache, dizziness, ataxia, nystagmus, paresthesia, confusion, difficulty concentrating, impaired memory, mental slowing, speech abnormalities, difficulty in verbal expression, agitation and/or irritability, depression, insomnia, anxiety, nervousness, schizophrenic and/or schizophreniform behavior, somnolence, fatigue, tiredness, flu-like syndrome, ecchymosis, rhinitis, weight loss, rash, diplopia.^{1 2 3 8 9}

Interactions for Zonisamide

Does not appear to inhibit CYP isoenzymes in vitro;^{1 2 3} metabolic pathways include metabolism by CYP3A4.¹

Drugs Metabolized by or Affecting Hepatic Microsomal Enzymes

Potential pharmacokinetic interaction (altered serum concentrations of zonisamide) with inhibitors or inducers of CYP3A4.^{1 2}

Does not appear to interfere with metabolism of drugs metabolized by CYP isoenzymes.^{1 2 3}

Anticonvulsants

Other anticonvulsants may alter pharmacokinetics of zonisamide.^{1 2} (See Specific Drugs under Interactions.)

Drugs Predisposing to Heat-related Disorders

Increased risk of oligohidrosis and hyperthermia with drugs that predispose to heat-related disorders (e.g., carbonic anhydrase inhibitors, drugs with anticholinergic activity).^{1 13 26}

Specific Drugs

Drug	Interaction	Comments
Acetazolamide and other carbonic anhydrase inhibitors	Possible increased risk of developing metabolic acidosis and heat-related disorders during concurrent administration1 13 19 26
Carbamazepine	Possible decrease in plasma zonisamide concentrations;1 2 3 no change in steady-state plasma carbamazepine concentrations1 2 8	Increase in zonisamide dosage may be required2
Oral contraceptives	Pharmacokinetic interaction unlikely28
Phenobarbital	Zonisamide half-life decreased1
Phenytoin	Possible decrease in plasma zonisamide concentrations;1 2 3 no change in steady-state plasma phenytoin concentrations1 2 8	Increase in zonisamide dosage may be required2
Valproic acid	No change in steady-state plasma concentrations of valproic acid1 2 8

Zonisamide Pharmacokinetics

Absorption

Bioavailability

Rapidly and almost completely absorbed following oral administration, with nearly 100% oral bioavailability.^{2 3} Peak plasma concentrations attained within 2–6 hours after oral administration.¹

Food

Food delays the time to peak plasma concentration but does not affect bioavailability.¹

Distribution

Extent

Extensively binds to erythrocytes, resulting in an 8-fold higher concentration of zonisamide in erythrocytes than in plasma.¹

Crosses the placenta;¹⁸ distributed into breast milk.^{18 19}

Plasma Protein Binding

Approximately 40%.¹

Elimination

Metabolism

Undergoes acetylation to form N-acetyl zonisamide, subsequent reduction to form 2-sulfamoylacetyl phenol, and further glucuronide conjugation.^{1 3} The reduction of N-acetyl zonisamide is mediated by CYP3A4.^{1 2 3}

Does not induce own metabolism.¹

Elimination Route

Excreted principally in urine as unchanged drug and a glucuronide metabolite.^{1 2 3}

Half-life

About 63 hours.^{1 3}

Special Populations

In patients with marked renal impairment (Cl_cr≤ 20 mL/minute), AUC was increased by 35%.¹ Renal clearance decreases with decreasing renal function.¹

In patients with hepatic impairment, pharmacokinetics not studied to date.¹

Clearance of zonisamide may be increased at the end of the second trimester in pregnant women.²⁰

Pharmacokinetics were similar in geriatric and young healthy volunteers in single-dose studies.¹ (See Geriatric Patients under Dosage and Administration.)

Stability

Storage

Oral

Capsules

Dry place at 25°C (may be exposed to 15–30°C); protect from light.¹

Actions

• 
  

  Exact mechanism of action is not known; anticonvulsant activity may be associated with the drug’s sodium- and calcium-channel blocking activities.^{1 2 3 9}

  
  


• 
  

  May potentiate dopaminergic and serotonergic neurotransmission^{1 2 3} but does not appear to potentiate the synaptic activity of GABA.¹

  
  


• 
  

  Exhibits weak inhibition of carbonic anhydrase activity;^{1 2 3} not thought to contribute substantially to anticonvulsant activity.¹

  
  

Advice to Patients

• 
  

  Importance of providing copy of written patient information (medication guide) each time zonisamide is dispensed.^{1 21}

  
  


• 
  

  Risk of serious skin rash that can cause death; these skin reactions are more likely to happen within the first 4 months of starting therapy, but may occur later.¹ Importance of immediately contacting clinician if skin rash occurs.¹

  
  


• 
  

  Importance of patients being aware that zonisamide can prevent sweating, which makes it harder for the body to cool down when it gets very hot; this is more likely to occur in warmer weather, in children, and during physical exercise.^{1 13 26} Importance of avoiding exposure to heat, maintaining adequate hydration, and informing clinicians immediately if fever or increased body temperature and/or decreased sweating occurs, particularly in children or in hot weather.^{1 13 26}

  
  


• 
  

  Risk of blood cell abnormalities such as reduced RBC and WBC counts.¹ Importance of contacting clinician if fever, sore throat, sores in the mouth, or unusual bruising occurs.¹

  
  


• 
  

  Risk of suicidality (anticonvulsants, including zonisamide, may increase risk of suicidal thoughts or actions in about 1 in 500 people).^{1 15 21} Importance of patients, family, and caregivers being alert to day-to-day changes in mood, behavior, and actions and immediately informing clinician of any new or worrisome behaviors (e.g., talking or thinking about wanting to hurt oneself or end one’s life, withdrawing from friends and family, becoming depressed or experiencing worsening of existing depression, becoming preoccupied with death and dying, giving away prized possessions).^{1 15}

  
  


• 
  

  Importance of patients being aware that zonisamide may cause metabolic acidosis.¹⁹ Importance of patients being aware that blood tests to measure serum bicarbonate levels may be performed.¹⁹ Symptoms of metabolic acidosis include breathing fast (hyperventilation), fatigue, and loss of appetite; more severe symptoms include an irregular heart beat or unconsciousness.¹⁹

  
  


• 
  

  May cause drowsiness, especially at higher dosages.¹ Avoid driving or operating machinery while taking zonisamide until experience with the drug’s effects has been established.¹

  
  


• 
  

  Risk of kidney stones.¹ Importance of informing patients that increasing fluid intake (i.e., by drinking 6–8 glasses of water a day) and urine output may reduce the risk of stone formation, particularly in those with predisposing factors.¹ Importance of immediately reporting symptoms of kidney stones (e.g., sudden back pain, abdominal pain, and/or blood in urine) to clinician.¹

  
  


• 
  

  Importance of immediately reporting worsening of seizures and severe muscle pain and/or weakness to clinician.¹

  
  


• 
  

  Importance of women informing clinicians if they are or plan to become pregnant.^{1 19} Importance of informing women who are or plan to become pregnant that zonisamide may cause metabolic acidosis, which may negatively affect fetal development during pregnancy.¹⁹ Importance of clinicians informing women about the existence of and encouraging enrollment in pregnancy registries (see Pregnancy under Warnings/Precautions: Specific Populations, in Cautions).¹

  
  


• 
  

  Importance of informing nursing women and those who plan to breast-feed that zonisamide can appear in the breast milk, and that the effects of this exposure on the infant are unknown.¹⁹ Importance of women informing clinicians if they plan to breast-feed.^{1 19}

  
  


• 
  

  Importance of swallowing zonisamide capsules whole and not biting into or breaking into the capsules; zonisamide may be taken with or without food.¹

  
  


• 
  

  Importance of informing patients not to stop taking zonisamide without talking to their clinician since stopping the drug suddenly can cause serious problems, including seizures.¹

  
  


• 
  

  Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription drugs, OTC drugs, and special diets (e.g., ketogenic diet), as well as any concomitant illnesses (e.g., liver disease, kidney disease, severe lung disorders, diarrhea, surgery, depression, bipolar disorder) or family history of suicidality or bipolar disorder.^{1 13 19}

  
  


• 
  

  Importance of informing patients of other important precautionary information.¹ (See Cautions.)

  
  

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Zonisamide

Routes	Dosage Forms	Strengths	Brand Names	Manufacturer
Oral	Capsules	25 mg*	Zonegran	Eisai
			Zonisamide Capsules
		50 mg*	Zonisamide Capsules
		100 mg*	Zonegran	Eisai
			Zonisamide Capsules

Comparative Pricing

This pricing information is subject to change at the sole discretion of DS Pharmacy. This pricing information was updated 10/2011. Actual costs to patients will vary depending on the use of specific retail or mail-order locations and health insurance copays.

Zonegran 100MG Capsules (EISAI): 30/$131.99 or 90/$380.98

Zonegran 25MG Capsules (EISAI): 30/$39.99 or 90/$97.97

Zonisamide 100MG Capsules (GLENMARK PHARMACEUTICALS): 30/$59.99 or 90/$169.97

Zonisamide 25MG Capsules (GLENMARK PHARMACEUTICALS): 100/$49.99 or 300/$139.98

Zonisamide 50MG Capsules (GLENMARK PHARMACEUTICALS): 100/$91.99 or 300/$259.98

Disclaimer

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. and Drugs.com represent that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. and Drugs.com make no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. and Drugs.com do not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS Drug Information. © Copyright, 1959-2011, Selected Revisions October 27, 2011. American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland 20814.

† Use is not currently included in the labeling approved by the US Food and Drug Administration.

References

1. Elan Pharma International Ltd, (manufacturer) and Eisai Inc. (distributor). Zonegran (zonisamide) capsules prescribing information. Woodcliff Lake, NJ; 2009 Apr.

2. Anon. Zonisamide (Zonegran) for epilepsy. Med Lett Drugs Ther. 2000; 42:94-5. [PubMed 11015160]

3. Schachter SC. The next wave of anticonvulsants: focus on levetiracetam, oxcarbazepine and zonisamide. Drugs. 2000; 14:229-49.

4. Leppik IE, Willmore LJ, Homan RW et al. Efficacy and safety of zonisamide: results of a multicenter study. Epilepsy Res. 1993; 14:165-73. [PubMed 8453952]

5. Berent S, Sackellares JC, Giordani B et al. Zonisamide (CI-912) and cognition: results from preliminary study. Epilepsia. 1987; 28:61-7. [PubMed 3098556]

6. Sackellares JC, Donofrio PD, Wagner JG et al. Pilot study of zonisamide (1,2-benzisoxazole-3-methanesulfonamide) in patients with refractory partial seizures. Epilepsia. 1985; 26:206-11. [PubMed 3924586]

7. Wilensky AJ, Friel PN, Ojemann LM Et al. Zonisamide in epilepsy: a pilot study. Epilepsia. 1985; 26:212-20. [PubMed 4006880]

8. Schmidt D, Jacob R, Loiseau P et al. Zonisamide for add-on treatment of refractory partial epilepsy: a European double-blind trial. Epilepsy Res. 1993 May; 15:67-73.

9. Oommen KJ, Mathews S. Zonisamide: a new antiepileptic drug. Clin Neuropharmacol. 1999; 22:192-200. [PubMed 10442247]

10. Leppik IE. Zonisamide. Epilepsia. 1999; 40(Suppl 5):S23-9. [IDIS 435526] [PubMed 10530691]

11. Okumura A, Hayakawa F, Kuno K et al. Oligohidrosis caused by zonisamide. No To Hattatsu. 1996; 28:44-7. [PubMed 8579857]

12. Kubota M, Nishi-Nagase M, Sakakihara Y et al. Zonisamide-induced urinary lithiasis in patients with intractable epilepsy. Brain Dev. 2000; 22:230-3. [PubMed 10838109]

13. O’Brien C. Dear doctor letter regarding oligohidrosis and hyperthermia in pediatric patients. San Diego, CA: Elan Pharmaceuticals; 2002. From the FDA website.

14. Food and Drug Administration. FDA Alert: Suicidality and antiepileptic drugs. Rockville, MD; 2008 Jan 31. From the FDA website.

15. Food and Drug Administration. FDA Alert: Information for healthcare professionals: suicidality and antiepileptic drugs. Rockville, MD; 2008 Jan 31. From the FDA website.

16. Food and Drug Administration. FDA News: FDA alerts health care providers to risk of suicidal thoughts and behavior with antiepileptic medications. Rockville, MD; 2008 Jan 31. From the FDA website.

17. Kalinin VV. Suicidality and antiepileptic drugs: is there a link?. Drug Saf. 2007; 30:123-42. [PubMed 17253878]

18. Kawada K, Itoh S, Kusaka T et al. Pharmacokinetics of zonisamide in perinatal period. Brain Dev. 2002; 24:95-7. [PubMed 11891100]

19. Food and Drug Administration. FDA Alert: Information for healthcare professionals: zonisamide (marketed as Zonegran, and generics). Rockville, MD; 2009 Feb 23. From the FDA website.

20. Oles KS, Bell WL. Zonisamide concentrations during pregnancy. Ann Pharmacother. 2008; 42:1139-41. [PubMed 18577760]

21. Food and Drug Administration. Suicidal behavior and ideation and antiepileptic drugs: update 5/5/2009. Rockville, MD; 2009 May 5. From the FDA website.

22. Lee YJ, Kang HC, Seo JH et al. Efficacy and tolerability of adjunctive therapy with zonisamide in childhood intractable epilepsy. Brain Dev. 2009; Mar 20:[epub ahead of print].

23. Coppola G, Grosso S, Verrotti A et al. Zonisamide in children and young adults with refractory epilepsy: an open label, multicenter Italian study. Epilepsy Res. 2009; 83:112-6. [PubMed 19081227]

24. Santos CC, Brotherton T. Use of zonisamide in pediatric patients. Pediatr Neurol. 2005; 33:12-4. [PubMed 15876518]

25. Wilfong AA. Zonisamide monotherapy for epilepsy in children and young adults. Pediatr Neurol. 2005; 32:77-80. [PubMed 15664764]

26. Low PA, James S, Peschel T et al. Zonisamide and associated oligohidrosis and hyperthermia. Epilepsy Res. 2004; 62:27-34. [PubMed 15519129]

27. Shinnar S, Pellock JM, Conry JA. Open-label, long-term safety study of zonisamide administered to children and adolescents with epilepsy. Eur J Paediatr Neurol. 2009; 13:3-9. [PubMed 18343174]

28. Griffith SG, Dai Y. Effect of zonisamide on the pharmacokinetics and pharmacodynamics of a combination ethinyl estradiol-norethindrone oral contraceptive in healthy women. Clin Ther.. 2004; 26:2056-65.

More Zonisamide resources

• Zonisamide Side Effects (in more detail)
• Zonisamide Dosage
• Zonisamide Use in Pregnancy & Breastfeeding
• Drug Images
• Zonisamide Drug Interactions
• Zonisamide Support Group
• 20 Reviews for Zonisamide - Add your own review/rating

• Zonisamide MedFacts Consumer Leaflet (Wolters Kluwer)


• Zonisamide Professional Patient Advice (Wolters Kluwer)


• zonisamide Advanced Consumer (Micromedex) - Includes Dosage Information


• Zonegran Prescribing Information (FDA)


• Zonegran Consumer Overview

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