Primidone (PRIM i done) has been approved by the FDA to treat tonic-clonic (grand mal), temporal lobe, and focal seizures. It may also control tonic-clonic seizures that are resistant to other anticonvulsant treatments.

Your epilepsy treatment should always be discussed with your healthcare provider before use. Based on their judgment and knowledge, a drug may be prescribed for other epilepsy types not included in the indications. For more information, please see the prescribing information.

How can you take primidone? (Available formulations)

Primidone is available as a tablet.

Who should not take primidone?

If you are allergic to primidone or any of the inactive ingredients, then you should not take it. Primidone should not be taken if you have porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system).

Other considerations may influence whether you should take primidone. Tell your healthcare provider if you:

  • have or have had depression, mood problems, or suicidal thoughts or behavior.
  • are pregnant or plan to become pregnant.
  • are breastfeeding or plan to breastfeed.

What is important to know about taking primidone?

Do not stop taking primidone suddenly unless directed to do so by your healthcare provider.

As with all antiseizure medications, primidone should be withdrawn gradually to minimize the risk of causing or worsening seizures or status epilepticus. You should not stop using primidone suddenly unless your healthcare provider tells you to stop the medicine because of a serious side effect.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Taking primidone with certain other medicines may cause side effects or affect how well they work. Do not start or stop other medicines without talking to your healthcare provider. Especially tell your healthcare provider if you take: drugs that cause sleepiness or dizziness or alcohol.

Women or those who are/plan to become pregnant
Use in pregnancy

At this time, there is not enough evidence regarding developmental risks associated with the use of primidone in pregnant people. However, having a seizure during pregnancy could harm both the pregnant individual and the baby. Tell your healthcare provider right away if you become pregnant. Do not start or stop taking seizure medication during pregnancy without your healthcare provider’s advice.

If you become pregnant while taking primidone, talk to your healthcare provider about registering with the North American Antiepileptic Drug (NAAED) Pregnancy Registry. The purpose of this registry is to collect information about the safety of antiseizure medicine during pregnancy. You can enroll in this registry by calling 1-888-233-2334.

Use during breastfeeding

Primidone is present in breast milk. It is unknown if there are effects on the breastfed infant, or if primidone impacts milk production. Talk to your healthcare provider about the risks. Your healthcare provider will consider the developmental and health benefits of breastfeeding along with your need for primidone and the potential effect on the infant from primidone or from your epilepsy.

What are the side effects of primidone?

Primidone is approved by the FDA because it is safe and effective for the majority of people who take it. However, there are risks associated with all medicines. Some side effects caused by primidone can be very serious, and even life-threatening. It is important to be informed about these serious reactions and to be aware of their symptoms.

Common side effects

The most common side effects that were reported in studies of primidone are problems with movement and balance (ataxia) and vertigo (off-balance sensation).

Rare, but serious side effects
Suicidal thoughts or behaviors

Studies have found that people who take antiseizure medications including primidone may have suicidal thoughts or behaviors, which occur in approximately 1 in 500 patients. If you experience any thoughts or impulses to hurt yourself, you should contact your healthcare provider immediately.