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Mysoline

Generic Name: primidone (PRIM i done)
Brand Name: Mysoline

Medically reviewed on December 15, 2017

What is Mysoline?

Mysoline is an anti-epileptic drug, also called an anticonvulsant.

Mysoline is used to control seizures.

Mysoline may also be used for other purposes not listed in this medication guide.

Important Information

You should not use this medication if you are allergic to Mysoline or phenobarbital (Luminal, Solfoton), or if you have porphyria.

Before taking this medication, tell your doctor if you are allergic to any drugs, or if you are pregnant or breast-feeding.

You may have thoughts about suicide while taking this medication. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, depression, anxiety, or if you feel agitated, hostile, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

If you are taking Mysoline to prevent seizures, keep taking the medication even if you feel fine. You may have an increase in seizures if you stop taking this medicine. Follow your doctor's instructions.

To be sure this medication is helping your condition, your blood may need to be tested on a regular basis. Do not miss any scheduled appointments.

Do not change your dose of primidone without your doctor's advice. Tell your doctor if the medication does not seem to work as well in treating your condition.

Carry an ID card or wear a medical alert bracelet stating that you are taking Mysoline, in case of emergency. Any doctor, dentist, or emergency medical care provider who treats you should know that you are taking a seizure medication.

Before taking this medicine

You should not use this medication if you are allergic to Mysoline or phenobarbital (Luminal, Solfoton), or if you have porphyria.

You may have thoughts about suicide while taking this medication. Tell your doctor if you have new or worsening depression or suicidal thoughts during the first several months of treatment, or whenever your dose is changed.

Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

Before taking this medication, tell your doctor if you are allergic to any drugs, or if you are pregnant or breast-feeding.

Mysoline may cause harm to an unborn baby, but having a seizure during pregnancy could harm both the mother and the baby. Do not start taking this medicine during pregnancy without your doctor's advice.

If you become pregnant while taking Mysoline, do not stop taking it without telling your doctor. Seizure control is very important during pregnancy and the benefits of preventing seizures may outweigh any risks posed by taking this medicine.

If you have taken Mysoline during pregnancy, be sure to tell the doctor who delivers your baby about your this medicine use. Both you and the baby may need to receive medications to prevent excessive bleeding during delivery and just after birth.

Primidone can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take Mysoline?

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Mysoline is usually taken 2 to 4 times daily. If you are switching to this medicine from another seizure medication, you may need to start taking this medicine only at bedtime. Follow your doctor's instructions.

If you are taking Mysoline to treat seizures, keep taking the medication even if you feel fine. You may have an increase in seizures if you stop taking this medicine. Follow your doctor's instructions.

To be sure this medication is helping your condition, your blood may need to be tested on a regular basis. Do not miss any scheduled appointments.

Do not change your dose of primidone without your doctor's advice. Tell your doctor if the medication does not seem to work as well in treating your condition.

Carry an ID card or wear a medical alert bracelet stating that you are taking Mysoline, in case of emergency. Any doctor, dentist, or emergency medical care provider who treats you should know that you are taking a seizure medication.

Store Mysoline at room temperature away from moisture, light, and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of Mysoline.

Symptoms of a Mysoline overdose are not known.

What should I avoid while taking primidone?

Follow your doctor's instructions about any restrictions on food, beverages, or activity while you are using Mysoline.

Mysoline side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, depression, anxiety, or if you feel agitated, hostile, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have any of these serious side effects:

  • slurred speech;

  • loss of balance or coordination;

  • easy bruising or bleeding; or

  • unusual weakness.

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Mysoline?

There may be other drugs that can interact with Mysoline. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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