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ZARONTIN 250 MG

ETHOSUXIMIDE : 250 MG · DIN 00022799 · SEARCHLIGHT PHARMA INC

Health Canada status: MARKETED

What is ZARONTIN?

ZARONTIN 250 MG contains ETHOSUXIMIDE : 250 MG. It is listed in the Health Canada Drug Product Database under DIN 00022799, held by SEARCHLIGHT PHARMA INC, supplied as CAPSULE for ORAL administration. Health Canada currently lists it as marketed, status dated 11-Oct-2022. Nexara Health is a licensed Canadian wholesale distributor (DEL 3-002896-A) and can source this product for hospitals, pharmacies and clinics. Availability and lead time are confirmed per order.

What is ZARONTIN used for?

ZARONTIN / ZARONTIN SYRUP (ethosuximide) is indicated for the control of absence (petit mal) epilepsy.

Authorized indication as written in the Health Canada product monograph. For healthcare professionals and licensed purchasers; this is not medical advice.

Product details and regulatory record

DIN00022799
Brand nameZARONTIN
Generic / active ingredientETHOSUXIMIDE : 250 MG
ManufacturerSEARCHLIGHT PHARMA INC
Strength250 MG
Dosage formCAPSULE
Route of administrationORAL
SchedulePrescription
ATC codeN03AD01 ETHOSUXIMIDE
AHFS class28:12.12
BiosimilarNo
Health Canada statusMARKETED
Status date11-Oct-2022
Original market date1951-12-31 00:00:00

How is it administered?

Initial dose: children aged 3 to 6 years, 250 mg daily; older patients, 500 mg daily in divided doses. The dose thereafter must be individualized according to response and tolerance. Dosage should be increased by small increments: e.g. increase daily dose by 250 mg every 4 to 7 days until control is achieved with minimal side effects. Daily dosage of 1 to 1.5 g in divided doses frequently controls seizures; however, it may be necessary to exceed this amount by slow increases and careful evaluation of patient's response. Dosage exceeding 1.5 g daily, in divided doses, should be administered only under the strictest supervision of the physician. The optimal dose for most children is 20 mg/kg/day. Ethosuximide can be taken with or without food. For syrup, advise the patient to carefully measure the dose using a measuring device/spoon. A household spoon should not be used to avoid dosing errors. In case of missed dose, the next dose should be taken as scheduled. A double dose should not be taken. Abrupt withdrawal of anticonvulsant medication may precipitate absence (petit mal) status. Patients taking ethosuximide should be advised of the importance of adhering strictly to the prescribed dosage regimen.

Included because it drives pack selection and wastage. Consult the monograph.

How is it stored and handled?

Store ZARONTIN capsules between 15 and 25 °C and protect from heat. Store ZARONTIN SYRUP between 15 and 25 °C and protect from freezing and light. Keep out of the reach and sight of children. Do NOT keep outdated medicine or medicine no longer needed. Any outdated or unused medicine should be returned to your pharmacist.

How is it supplied?

ZARONTIN: 250 mg ethosuximide per capsule. Available in bottles of 100. ZARONTIN SYRUP: Each 5 mL contains 250 mg ethosuximide. Available in bottles of 500 mL.

Contraindications

ZARONTIN / ZARONTIN SYRUP is contraindicated in patients who are hypersensitive to ethosuximide or to any ingredient in the formulation, including any non-medicinal ingredient, or component of the container. ZARONTIN / ZARONTIN SYRUP should not be used in patients who are hypersensitive to succinimides or components of these products.

Warnings and precautions

Blood dyscrasias, including with fatal outcomes, have been reported to be associated with the use of ethosuximide; therefore, periodic blood counts should be performed. Should signs and/or symptoms of infection (e.g., sore throat, fever) develop, blood count determinations should be considered at that point. Patients should be instructed to promptly contact their physician if they develop signs and/or symptoms (e.g., sore throat, fever) suggesting an infection. Drug-induced immune thrombocytopenia (DITP) has been reported with ethosuximide. When DITP is suspected, discontinue ZARONTIN / ZARONTIN SYRUP, monitor serial platelet counts, and treat as appropriate. Avoid future use of ZARONTIN / ZARONTIN SYRUP in patients with history of ethosuximide-induced DITP. Ethosuximide may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a motor vehicle or other such activity requiring alertness; therefore the patient should be cautioned accordingly. Ethosuximide is capable of producing morphological and functional changes in the animal liver. In humans, abnormal liver function studies have been reported. Administer ethosuximide with extreme caution to patients with known liver disease. Periodic liver function studies are advised for all patients receiving the drug. Case of systemic lupus erythematosus have been reported with the use of ethosuximide. The physician should be alert to this possibility. Ethosuximide, when used alone in mixed types of epilepsy, may increase the frequency of grand mal seizures in some patients. Suicidal ideation and behavior have been reported in patients treated with antiepileptic agents in several indications. All patients treated with antiepileptic drugs, irrespective of indication, should be monitored for sign of suicidal ideation and behavior and appropriate treatment should be considered. Patients (and caregivers of patients) should be advised to seek medical advice should signs of suicidal ideation or behavior emerge. Serious dermatologic reactions, including Stevens-Johnson syndrome (SJS), have been reported with ethosuximide treatment. SJS can be fatal. ZARONTIN / ZARONTIN SYRUP should be discontinued at the first sign of a rash, unless the rash is clearly not drug-related. If signs or symptoms suggest SJS, use of this drug should not be resumed and alternative therapy should be considered. Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), also known as multi organ hypersensitivity, has occurred with ZARONTIN / ZARONTIN SYRUP. Some of these events have been fatal or life-threatening. If such signs or symptoms are present, the patient should be evaluated immediately. ZARONTIN / ZARONTIN SYRUP should be discontinued if an alternative etiology for the signs or symptoms cannot be established.

What can be used instead?

Other Canadian products sharing ATC code N03AD01 ETHOSUXIMIDE. 4 of 4 DINs in this group are currently marketed — marketed products are listed first, because that is what can actually be bought. These tables describe supply, not clinical equivalence: substitution rests with the prescriber or pharmacist, and interchangeability is determined provincially.

ProductStrengthFormManufacturerHealth Canada statusDIN
MAR-ETHOSUXIMIDE250 MGCAPSULEMARCAN PHARMACEUTICALS INCMARKETEDDIN 02545772
ODAN-ETHOSUXIMIDE250 MGCAPSULEODAN LABORATORIES LTDMARKETEDDIN 02547171
ZARONTIN SYRUP250 MG / 5 MLSYRUPSEARCHLIGHT PHARMA INCMARKETEDDIN 00023485

Who else supplies ETHOSUXIMIDE worldwide?

Nexara tracks national medicine registries and published price lists across multiple markets. ETHOSUXIMIDE appears in 16 registered pack listings across 7 markets, published on 7 different national price bases. Where a Canadian route is closed, that is where an alternative route of supply starts — subject to the import rules in both countries.

Registered listings are not stock. Ask us to confirm what can actually be sourced for your order.

How can I get it?

Nexara Health supplies this product to licensed Canadian buyers — pharmacies, hospitals, clinics, licensed distributors, and clinical trial sponsors or their CROs. We confirm stock, pack size, expiry and pricing at the time of quotation. If the product is on backorder or in shortage, we identify equivalent alternatives and import options where permitted.

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Ordering questions

Who can buy this from Nexara?

Licensed entities only. Nexara holds Health Canada establishment licence DEL 3-002896-A and ships only to a licensed address.

Is there a minimum order?

Yes, set per product line and per pack multiple rather than on the order total, so you are never asked to buy a part-pack. The minimum for this line is confirmed with your quote.

What is the lead time?

Confirmed per order at quotation, and it depends on current stock position and whether the product is in shortage.

Can Nexara supply this for a clinical trial?

Yes — comparator and background-therapy supply, including sourcing from other markets where a Canadian pack will not satisfy the protocol. Clinical trial supply.

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Health Canada Drug Product Database (DPD), DIN 00022799. Last reviewed 2026-09-08. Nexara Health is a licensed wholesaler and supplies licensed entities only; consumer orders are routed to a partner pharmacy.