Zonisamide
Zonisamide is an anti-seizure medicine used as add-on treatment for partial-onset (focal) seizures in people with epilepsy, available as capsules and as an oral suspension.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 35 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
Zonisamide is a long-familiar add-on medicine for partial-onset (focal) seizures in adults with epilepsy, likely working by blocking sodium and calcium channels; it has been on the U.S. market since about 2000 and is available as a generic. Most people tolerate it reasonably well with slow dose increases, though sleepiness, dizziness, loss of appetite and foggy memory or concentration are common. Because it is a sulfa drug, get medical help right away for any new rash, and report blurred vision, eye pain, mood changes, or fast breathing with unusual tiredness, a sign of too much acid in the blood. Never stop it suddenly, which can bring on more seizures.
Clinical pearls
- Drink plenty of water through the day, because zonisamide raises the risk of kidney stones.
- It can reduce sweating, so watch for overheating in hot weather or hard exercise, especially in children.
- Make sure every prescriber knows, since adding topiramate or acetazolamide worsens blood acid levels and kidney stone risk.
- Use effective birth control during treatment and for one month after stopping, as animal studies suggest possible harm to a baby.
Patient information guide A plain-language walkthrough of Zonisamide, written from its FDA label.
What Zonisamide is used for
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Zonisamide is used as add-on seizure treatment.
- Zonegran (oral capsule): add-on therapy for partial seizures in adults with epilepsy.
- Zonisamide (oral capsule): add-on therapy for partial seizures in adults with epilepsy.
- Zonisade (oral suspension): add-on therapy for partial-onset seizures in adults and patients 16 years and older.
How Zonisamide works
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The exact way zonisamide prevents seizures is unknown. Lab studies suggest it blocks sodium channels and certain calcium channels in nerve cells. This steadies the cell membranes and quiets the overactive, synchronized firing behind seizures.
It also affects dopamine and serotonin signaling and is a carbonic anhydrase inhibitor, which can lead to metabolic acidosis.
Zonisamide dosage
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Zonisamide is taken by mouth once or twice a day, with or without food. Doses are usually raised slowly, with at least two weeks at each step, because the drug stays in the body a long time.
- Zonegran and zonisamide capsules: swallow whole.
- Zonisade: shake well and use an accurate measuring device, not a household teaspoon. Discard 30 days after opening.
- Don't stop suddenly. Your doctor will lower the dose gradually.
Follow your prescriber and label directions.
Dosing details from the FDA-approved label
From the Zonisamide prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.
- Zonisade (oral suspension) – recommended dosage
- Initial dosage 100 mg daily
- May be increased by 100 mg daily every two weeks, based on clinical response and tolerability, to 400 mg daily
- Administer once or twice daily with or without food
- Maximum: 600 mg daily (for patients tolerating 400 mg daily who require further reduction of seizures); evidence from controlled trials shows no suggestion of increasing response above 400 mg/day
- Shake well before every administration; measure with an accurate measuring device (not a household teaspoon); discard unused portion 30 days after first opening the bottle
- Zonegran / zonisamide capsules – adjunctive therapy for partial seizures in adults over age 16
- Initial dose 100 mg daily
- After two weeks, may be increased to 200 mg/day for at least two weeks
- It can be increased to 300 mg/day and 400 mg/day, with the dose stable for at least two weeks at each level
- Administered once or twice daily
- Capsules swallowed whole
- Maximum: Doses of 100 to 600 mg/day are effective, but no suggestion of increasing response above 400 mg/day; little experience with doses greater than 600 mg/day
- Can be taken with or without food; safety and efficacy in pediatric patients below age 16 not established
- Patients with renal or hepatic disease
- Should be treated with caution
- Might require slower titration and more frequent monitoring
- Zonisamide is metabolized in the liver and excreted by the kidneys
Read the label’s full dosing text
DOSAGE AND ADMINISTRATION Zonisamide capsules are recommended as adjunctive therapy for the treatment of partial seizures in adults. Safety and efficacy in pediatric patients below the age of 16 have not been established. Zonisamide capsules should be administered once or twice daily, using 25 mg, 50 mg or 100 mg capsules. Zonisamide capsules are given orally and can be taken with or without food. Capsules should be swallowed whole. Adults over Age 16: The prescriber should be aware that, because of the long half-life of zonisamide, up to two weeks may be required to achieve steady state levels upon reaching a stable dose or following dosage adjustment. Although the regimen described below is one that has been shown to be tolerated, the prescriber may wish to prolong the duration of treatment at the lower doses in order to fully assess the effects of zonisamide at steady state, noting that many of the side effects of zonisamide are more frequent at doses of 300 mg per day and above. Although there is some evidence of greater response at doses above 100 to 200 mg/day, the increase appears small and formal dose-response studies have not been conducted. The initial dose of zonisamide capsules should be 100 mg daily. After two weeks, the dose may be increased to 200 mg/day for at least two weeks. It can be increased to 300 mg/day and 400 mg/day, with the dose stable for at least two weeks to achieve steady state at each level. Evidence from controlled trials suggests that zonisamide capsules doses of 100 to 600 mg/day are effective, but there is no suggestion of increasing response above 400 mg/day (see CLINICAL PHARMACOLOGY, Clinical Studies subsection). There is little experience with doses greater than 600 mg/day. Patients with Renal or Hepatic Disease: Because zonisamide is metabolized in the liver and excreted by the kidneys, patients with renal or hepatic disease should be treated with caution, and might require slower titration and more frequent monitoring (see CLINICAL PHARMACOLOGY and PRECAUTIONS ).
Read the full Dosage and Administration section on DailyMed →
Zonisamide side effects
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The most common side effects in studies were:
Common side effects
- Sleepiness (somnolence)
- Loss of appetite
- Dizziness
- Poor balance or coordination (ataxia)
- Agitation or irritability
- Trouble with memory or concentration
- Headache
- Nausea
- Headache, nausea and abdominal pain
When to get medical help
- Get help right away for a new rash. It can be an early sign of a life-threatening skin reaction.
- Call your doctor for fever, swollen glands, or facial swelling, even without a rash. These can signal a serious allergic-type reaction (DRESS).
- Seek care for sudden blurred vision or eye pain. This can be a sign of acute myopia or glaucoma.
- Report any new or worsening depression, unusual mood or behavior changes, or thoughts of self-harm.
- Call your doctor for fast breathing, unusual tiredness, or loss of appetite. These can be signs of metabolic acidosis.
- Watch for decreased sweating and a high body temperature, especially in hot weather and in children.
- Report signs of kidney stones, or easy bruising and infections that suggest a blood problem.
Call your doctor right away for rash, fever with swollen glands, eye pain or vision changes, mood changes or self-harm thoughts, or signs of overheating.
Zonisamide warnings and precautions
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- Sulfonamide reactions: rare but sometimes fatal reactions, including severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis), blood disorders and liver injury.
- Rash: stop and call your doctor at the first sign unless clearly not drug-related.
- DRESS: fever, rash, swollen glands or facial swelling with organ involvement.
- Metabolic acidosis: blood bicarbonate should be checked before and during treatment. It can raise the risk of kidney stones, high ammonia and bone problems.
- Eye problems: acute myopia and secondary angle closure glaucoma, usually within the first month.
- Reduced sweating and high body temperature: seen mostly in children.
- Suicidal thoughts: all seizure medicines carry this risk.
- Stopping suddenly: may increase seizures.
Zonisamide interactions
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Tell your prescriber about everything you take. Key cautions:
- Alcohol and other CNS depressants: added drowsiness and thinking problems.
- Other carbonic anhydrase inhibitors (topiramate, acetazolamide, dichlorphenamide): can worsen acidosis, kidney stones and high ammonia.
- Anticholinergic drugs: may add to the risk of heat-related problems.
- Enzyme-inducing seizure medicines: speed up clearance of zonisamide.
Interactions listed in the FDA-approved label
From the Zonisamide prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.
- Alcohol or other CNS depressants: Concomitant use has not been evaluated in clinical studies; because of the potential of zonisamide to cause CNS depression and other cognitive and/or neuropsychiatric adverse events, caution is needed. Use zonisamide with caution if used in combination with alcohol or other CNS depressants.
- Other carbonic anhydrase inhibitors (e.g., topiramate, acetazolamide, dichlorphenamide): May increase the severity of metabolic acidosis and may also increase the risk of kidney stone formation or the risk of hyperammonemia. If given concomitantly, monitor the patient for the appearance or worsening of metabolic acidosis.
Read the label’s full interactions text
Drug Interactions with CNS Depressants: Concomitant administration of zonisamide and alcohol or other CNS depressant drugs has not been evaluated in clinical studies. 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. 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 or the risk of hyperammonemia. Therefore, if zonisamide is given concomitantly with another carbonic anhydrase inhibitor, the patient should be monitored for the appearance or worsening of metabolic acidosis (see CLINICAL PHARMACOLOGY, Interactions of Zonisamide with Other Carbonic Anhydrase Inhibitors subsection and WARNINGS, Metabolic Acidosis subsection and Hyperammonemia and Encephalopathy subsection). Carcinogenicity, Mutagenesis, Impairment of Fertility: No evidence of carcinogenicity was found in mice or rats following dietary administration of zonisamide for two years at doses of up to 80 mg/kg/day. In mice, this dose is approximately equivalent to the maximum recommended human dose (MRHD) of 400 mg/day on a mg/m 2 basis. In rats, this dose is 1 to 2 times the MRHD on a mg/m 2 basis. Zonisamide was mutagenic in an in vitro chromosomal aberration assay in CHL cells. Zonisamide was not mutagenic or clastogenic in other in vitro assays (Ames, mouse lymphoma tk assay, chromosomal aberration in human lymphocytes) or in the in vivo rat bone marrow cytogenetics assay.
Excerpted — the section continues on the label. Read the full Drug Interactions section on DailyMed →
Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.
Before taking Zonisamide
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- Don't use it if you are allergic to sulfonamides or zonisamide.
- Kidney or liver disease may call for slower dose increases and closer monitoring.
- Pregnancy: animal data show possible fetal harm. Use effective contraception during treatment and for one month after. Zonisamide levels may drop during pregnancy.
- Breastfeeding: it passes into milk. Watch the infant for poor feeding, weight loss, sleepiness, low muscle tone and fever.
- Under 16: safety and effectiveness are not established.
- Older adults: studies had too few people 65 and older to show differences.
Zonisamide overdose
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Overdose cases have caused central nervous system effects, including coma, slow heart rate, low blood pressure and slowed breathing. There is no specific antidote, and care is supportive. Contact a poison control center right away.
What Zonisamide does in the body
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As a carbonic anhydrase inhibitor, zonisamide can cause metabolic acidosis (acid buildup in the blood). It may also raise the risk of high blood ammonia and kidney stones.
How your body processes Zonisamide
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Zonisade reaches peak blood levels within about 0.5 to 5 hours. Food delays the peak but does not change how much is absorbed. Steady levels take about 14 days. Zonisamide is processed by the liver, including the CYP3A4 enzyme, and cleared mainly through the urine. Its half-life in plasma is about 63 hours, so it is long-acting. Severe kidney impairment raises drug levels by about 35%.
How to store Zonisamide
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Store at 20°C to 25°C (68°F to 77°F), excursions permitted from 15°C to 30°C (59°F to 86°F) . Protect from light.
Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
Supplements & herbs that interact with Zonisamide
206 supplements and herbal products have documented interactions with Zonisamide in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Major · 9
- Moderate · 157
- Minor · 40
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
Nutrient depletion considerations
Zonisamide has been associated with lower levels of 1 nutrient in the clinical literature. This does not mean a deficiency will occur — it means these may be worth discussing with your pharmacist or healthcare provider, especially with long-term use.
Educational information from a licensed clinical database (Natural Medicines) — not medical advice. Do not start or stop medications or supplements without professional guidance.
Zonisamide: pharmacist answers to common questions
Quick, plain-English answers to the questions patients ask most about Zonisamide — the kind of thing our pharmacy team would talk through with you at the counter.
What is zonisamide for?
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How should I take it?
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What side effects are normal?
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When should I call my doctor right away?
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Can I drink alcohol or take other medicines with it?
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What if I'm pregnant or planning to be?
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Is Zonisamide available over the counter?
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When was Zonisamide first available?
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Who makes Zonisamide?
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Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
More about Zonisamide on HelloPharmacist
Zonisamide forms and strengths (how it comes)
Zonisamide is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Capsule
How this form is used
- Zonegran is used as add-on therapy for partial seizures in adults with epilepsy.
- Zonisamide capsules are used as add-on therapy for partial seizures in adults with epilepsy.
- Zonegran is taken by mouth once or twice daily, with or without food.
- Zonegran capsules should be swallowed whole.
- Zonisamide capsules are taken by mouth once or twice daily, with or without food, and swallowed whole.
Oral suspension
How this form is used
- Zonisade is used as add-on therapy for partial-onset seizures in adults and patients 16 years and older.
- Zonisade is taken by mouth once or twice daily, with or without food.
- Shake Zonisade well before every dose.
- Measure Zonisade with an accurate device from your pharmacist, not a household teaspoon.
- Throw away unused Zonisade 30 days after first opening the bottle.
Zonisamide on the U.S. market: products, makers and brands
How Zonisamide appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
21 companies list 51 Zonisamide product records with the FDA, mostly as capsule, oral suspension; the earliest marketing or approval year on record is 2000. Brand names on the directory include Zonegran; the rest are generics.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Also listed with the FDA, not a patient dose form: Powder (18) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
How widely Zonisamide is used (Medicaid data)
A general measure of how commonly Zonisamide is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Zonisamide is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Zonisamide prescribed? Of the 1,601 medications we measure, Zonisamide ranks #291 by Medicaid prescriptions — more than 82% of them.
Utilization by Zonisamide product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
zonisamide 100 MG Oral Capsule Most dispensed
Summed across the 10 of 100 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 314285
zonisamide 50 MG Oral Capsule
Summed across the 6 of 32 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 403967
zonisamide 20 MG/ML Oral Suspension
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2606782
zonisamide 25 MG Oral Capsule
Summed across the 5 of 39 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 403966
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Zonisamide, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 22 of 172 listed Zonisamide NDCs with Medicaid activity.
Compare Zonisamide products
A representative set of FDA-listed product records for Zonisamide — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Capsule | ||||
| 100 mg | Oral | Advanced Rx of Tennessee, LLC | ANDA | View NDC → |
| 100 mg | Oral | Advanced Rx Pharmacy of Tennessee, LLC | ANDA | View NDC → |
| 25 mg | Oral | Advanz Pharma (US) Corp. | NDA | View NDC → |
| 100 mg | Oral | Advanz Pharma (US) Corp. | NDA | View NDC → |
| 100 mg | Oral | American Health Packaging | ANDA | View NDC → |
| 25 mg | Oral | Aurobindo Pharma Limited | ANDA | View NDC → |
| 50 mg | Oral | Aurobindo Pharma Limited | ANDA | View NDC → |
| 100 mg | Oral | Aurobindo Pharma Limited | ANDA | View NDC → |
| 100 mg | Oral | AvPAK | ANDA | View NDC → |
| 25 mg | Oral | BluePoint Laboratories | ANDA | View NDC → |
| 50 mg | Oral | BluePoint Laboratories | ANDA | View NDC → |
| 100 mg | Oral | BluePoint Laboratories | ANDA | View NDC → |
| 25 mg | Oral | Bryant Ranch Prepack × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Bryant Ranch Prepack | ANDA | View NDC → |
| 100 mg | Oral | Bryant Ranch Prepack × 4 listings | ANDA | View NDC → |
| 100 mg | Oral | Cipla USA Inc. | ANDA | View NDC → |
| 25 mg | Oral | Direct_Rx × 2 listings | ANDA | View NDC → |
| 25 mg | Oral | Exelan Pharmaceuticals, Inc. | ANDA | View NDC → |
| 50 mg | Oral | Exelan Pharmaceuticals, Inc. | ANDA | View NDC → |
| 100 mg | Oral | Exelan Pharmaceuticals, Inc. | ANDA | View NDC → |
| 25 mg | Oral | Glenmark Pharmaceuticals Inc., USA | ANDA | View NDC → |
| 50 mg | Oral | Glenmark Pharmaceuticals Inc., USA | ANDA | View NDC → |
| 100 mg | Oral | Glenmark Pharmaceuticals Inc., USA | ANDA | View NDC → |
| 100 mg | Oral | NCS HealthCare of KY, LLC dba Vangard Labs | ANDA | View NDC → |
| 100 mg | Oral | Preferred Pharmaceuticals, Inc. | ANDA | View NDC → |
| 100 mg | Oral | Preferred Pharmaceuticals Inc | ANDA | View NDC → |
| 100 mg | Oral | Proficient Rx LP × 3 listings | ANDA | View NDC → |
| 25 mg | Oral | Remedyrepack Inc. | ANDA | View NDC → |
| 50 mg | Oral | Remedyrepack Inc. | ANDA | View NDC → |
| 100 mg | Oral | Remedyrepack Inc. × 2 listings | ANDA | View NDC → |
| 25 mg | Oral | Sun Pharmaceutical Industries, Inc. | ANDA | View NDC → |
| 50 mg | Oral | Sun Pharmaceutical Industries, Inc. | ANDA | View NDC → |
| 100 mg | Oral | Sun Pharmaceutical Industries, Inc. | ANDA | View NDC → |
| 25 mg | Oral | Unichem Pharmaceuticals (USA), Inc. | ANDA | View NDC → |
| 50 mg | Oral | Unichem Pharmaceuticals (USA), Inc. | ANDA | View NDC → |
| 100 mg | Oral | Unichem Pharmaceuticals (USA), Inc. | ANDA | View NDC → |
| 25 mg | Oral | Viona Pharmaceuticals Inc | ANDA | View NDC → |
| 50 mg | Oral | Viona Pharmaceuticals Inc | ANDA | View NDC → |
| 100 mg | Oral | Viona Pharmaceuticals Inc | ANDA | View NDC → |
| 25 mg | Oral | Zydus Lifesciences Limited | ANDA | View NDC → |
| 50 mg | Oral | Zydus Lifesciences Limited | ANDA | View NDC → |
| 100 mg | Oral | Zydus Lifesciences Limited | ANDA | View NDC → |
| 💊Oral suspension | ||||
| 100 mg/5 mL | Oral | Azurity Pharmaceuticals, Inc. | NDA | View NDC → |
Showing 51 of 51 products — FDA National Drug Code Directory. See every product, package size and price: browse all 51 Zonisamide NDCs →
Zonisamide side effects reported to the FDA (FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Zonisamide — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Zonisamide in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
Zonisamide FDA approval history
How Zonisamide went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
Zonisamide recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
The FDA’s enforcement reports list 2 Zonisamide recalls since July 2021, covering 5 product listings. None of them is still listed as ongoing. A recall names specific lots from one company, so check the lot number on your own bottle rather than assuming every product is affected; your pharmacist can check whether your supply came from an affected lot.
- Zonisamide Capsules, USP, 100 mg, packaged in: a) 100-count bottle (NDC 68462-130-01); b) 500-count bottle (NDC 68462-130-05), Rx only, Manufactured by: Glenmark Pharmaceuticals, Inc., USA Monroe, NC… Lots: a) Lot #: 29200053, Exp 4/30/2023; b) Lot #: 29200054, Exp 4/30/2023 FDA record D-0793-2022 →
- Zonisamide Capsules, USP, 50 mg, packaged in 100-count bottles, Rx only, Manufactured by: Glenmark Pharmaceuticals, Inc., USA Monroe, NC 28110, Manufactured for: Glenmark Pharmaceuticals Inc., USA Ma… Lots: Lot #: 29200064, Exp 5/31/2023 FDA record D-0792-2022 →
- Zonisamide Capsules USP, 25 mg, packaged in 100-count bottles, Rx Only, Manufactured by: Glenmark Pharmaceuticals, Inc., USA Monroe, NC 28110, Manufactured for: Glenmark Pharmaceuticals Inc., USA Mah… Lots: Lot #: 29200052, Exp 4/30/2023 FDA record D-0791-2022 →
- Zonisamide Capsules USP 100 mg Rx Only Manufactured by: Glenmark Pharmaceuticals Inc., USA Monroe, NC 28110 Manufactured for: Glenmark Pharmaceuticals Inc., USA Mahwah, NJ 07430 a) 100 Capsules NDC 6… Lots: Lots: a) 29200014 Exp. 02/28/2023; 29200015 Exp. 03/31/2023; 29200016 Exp. 03/31/2023; 29200030 Exp. 05/31/2023; 29200031 Exp. 05/31/2023; 29200032 Exp. 05/31/2023; 29200033 Exp. 06/30/2023; 29200037 Exp. 06/30/2023; 29200038 Exp. 06/30/20… FDA record D-0826-2021 →
- Zonisamide Capsules USP 50 mg 100 Capsules Rx Only NDC 68462-129-01 Manufactured by: Glenmark Pharmaceuticals Inc., USA Monroe, NC 28110 Manufactured for: Glenmark Pharmaceuticals Inc., USA Mahwah, N… Lots: Lots: 29190043 Exp. 05/31/2022; 29190044 Exp. 05/31/2022; 29190045 Exp. 05/31/2022 FDA record D-0825-2021 →
Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 39998 3 dose forms · 5 strengths
-
Dose form (SCDF) Oral Capsule RxCUI 374625In current FDA listings -
Dose form (SCDF) Oral Suspension RxCUI 2606781In current FDA listingsClinical drug / strength (SCD) 20 MG/MLRxCUI 2606782 -
Dose form (SCDF) Oral Tablet RxCUI 375369No current FDA listingClinical drug / strength (SCD) 100 MGRxCUI 259224
Look up RxCUI 39998 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
Zonisamide supply and shortage status
Whether Zonisamide is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
Zonisamide brand names
Zonisamide is sold under one brand name in the FDA directory — Zonegran. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.
Who makes Zonisamide: manufacturers and labelers
21 companies list Zonisamide products with the FDA. By number of product records, the largest are Bryant Ranch Prepack, Remedyrepack Inc., Aurobindo Pharma Limited. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.
Zonisamide drug class (RxNorm)
Zonisamide belongs to the Anti-epileptic Agent class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
Sources for this Zonisamide page
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How this page is built
HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Concordia Pharmaceuticals Inc. is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →