Read the Medication Guide provided by your pharmacist before you start using primidone and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually 3 to 4 times daily. Take with food or milk if stomach upset occurs. Your doctor may direct you to start this medication at a low dose at bedtime and gradually increase your dose to prevent side effects such as drowsiness and dizziness. If you are changing from a different anticonvulsant to primidone, your doctor may direct you to continue your old medication and slowly lower the dose as you begin taking primidone. Follow your doctor's instructions carefully.

The dosage is based on your medical condition, age, weight, lab tests, and response to treatment. It may take several weeks to reach the best dose for you.

This medication works best when the amount of drug in your body is kept at a constant level. Take this drug at evenly spaced intervals. To help you remember, take it at the same times each day.

Do not stop taking this medication (and other anticonvulsant medications) without consulting your doctor. Your seizures may worsen or cause a very severe seizure that is difficult to treat (status epilepticus) when this drug is suddenly stopped.

If you suddenly stop using this medication, you may have withdrawal symptoms (such as anxiety, hallucinations, twitching, trouble sleeping). Withdrawal from primidone can be severe and include seizures and (rarely) death. To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used primidone for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.

Though it helps many people, this medication may sometimes cause addiction. This risk may be higher if you have a substance use disorder (such as overuse of or addiction to drugs/alcohol). Take this medication exactly as prescribed to lower the risk of addiction. Ask your doctor or pharmacist for more details.

Tell your doctor if your seizure control worsens (such as the number of seizures increases).