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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





This medication is used to treat seizure disorders.

How To Use

Take with food or milk if stomach upset occurs. Take this medication as prescribed. Do not stop taking this drug suddenly without consulting your doctor as seizures may occur. It is important to take all doses on time to keep the level of medication in your blood constant. Do this by taking doses at evenly spaced intervals throughout the day and night. While taking this medication, lab tests may be done, especially in the first few months, to check if the drug is working properly.

Side Effects

May cause drowsiness, dizziness, or blurred vision. Use caution performing tasks that require alertness. Other side effects include stomach upset, loss of appetite, headache, or hiccups. These should subside as your body adjusts to the medication. Notify your doctor if the following effects occur: seizures, vomiting, weakness, blurred vision, joint pain, unusual bleeding or bruising, depression, skin rash. If you notice other effects not listed above, contact your doctor or pharmacist.


Before you take ethosuximide, tell your doctor if you have: kidney or liver disease, blood problems. Use caution when drinking alcoholic beverages or taking over-the-counter sleeping pills or antihistamines (medication for colds or allergies); these substances can add to the drowsiness caused by ethosuximide. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. Ethosuximide is excreted into breast milk. Though, to date, no problems have been noted in nursing infants, consult your doctor before you breast-feed.

Drug Interactions

Tell your doctor of all prescription and nonprescription drugs you may use, especially of: anti-seizure drugs (e.g., phenytoin, primidone, valproic acid). This drug may interfere with the effectiveness of birth control pills. Discuss using other methods of birth control with your doctor. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea and vomiting.


It is recommended to wear or carry medication identification indicating you are taking this drug.

Missed Dose

If you miss a dose, take as soon as remembered; do not take if it is within 4 hours of the next dose, instead, skip missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (between 15 and 30 degrees C) away from moisture and sunlight. Do not store in the bathroom. Do not freeze liquid forms of this medication.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).