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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.





Primidone is used to treat a seizure disorder.



This medication may also be used to treat tremors.

How To Use

Take with food or milk if stomach upset occurs. The liquid form of this medication must be shaken well before measuring each dose. This medication must be taken 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. Take doses at evenly spaced intervals throughout the day and night.

Side Effects

May cause drowsiness or sleepiness. Other side effects include stomach upset, loss of appetite, clumsiness, or fatigue. If any of these effects persist or worsen, notify your doctor. Notify your doctor if the following effects occur: seizures, double vision, fever, sore throat, skin rash. In the unlikely event you have an allergic reaction to this drug, seek immediate medical attention. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially about: liver disease, lung disease, kidney disease, porphyria (a blood disorder), any allergies. Use caution when drinking alcoholic beverages because it may add to the drowsiness effect caused by primidone. Use caution performing tasks requiring alertness such as driving or using machinery because this drug often causes drowsiness. This drug is not recommended for use during pregnancy. Consult your doctor before using this drug. This drug is excreted into breast milk, although its effects on a nursing infant are unknown. Consult your doctor before you breast-feed.

Drug Interactions

Tell your doctor of all other medications you may use (both prescription and nonprescription), especially of: other seizure medications, steroids, warfarin, digoxin, griseofulvin, disulfiram, medication for depression, doxycycline, cyclosporine. Tell your doctor if you are taking any drugs that may add to primidone's drowsiness effects such as: narcotic pain medicines (e.g., codeine), muscle relaxants, alcoholic beverages, certain antihistamines (e.g., diphenhydramine). Primidone can decrease the effectiveness of birth-control pills. Consult your doctor about using other methods of birth control. 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 confusion, uncontrolled eye movement, and trouble breathing.


Do not allow anyone else to take this medication. Lab tests may be done, especially in the first few months, to check if the drug is working properly.

Missed Dose

If you miss a dose, take as soon as remembered unless it is within 1 hour of your next dose. If so, skip the missed dose and resume your usual dosing schedule. Do not double 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.

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).