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Mysoline

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

Medically reviewed by Drugs.com on Feb 18, 2019 – Written by Cerner Multum

What is Mysoline?

Mysoline is an anticonvulsant medicine that is used to control seizures.

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

Important Information

Some people have thoughts about suicide while taking Mysoline. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.

Do not stop using Mysoline suddenly, even if you feel fine. Stopping suddenly may cause increased seizures.

Before taking this medicine

You should not use Mysoline if you are allergic to Mysoline or phenobarbital, or if you have:

  • porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system).

Tell your doctor if you have ever had:

Some people have thoughts about suicide while taking Mysoline. Your doctor will need to check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.

Do not start or stop taking seizure medication during pregnancy without your doctor's advice. Having a seizure during pregnancy could harm both mother and baby. Tell your doctor right away if you become pregnant.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of primidone on the baby. Be sure to tell the doctor who delivers your baby about your Mysoline use. Both you and the baby may need to receive medications to prevent excessive bleeding during delivery and just after birth.

Stop breast-feeding if you notice unusual drowsiness in the nursing baby. Talk with your doctor about how best to feed your baby while taking Mysoline.

How should I take Mysoline?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

If you are switching to Mysoline from another seizure medication, you may need to start taking this medicine only at bedtime. Follow your doctor's instructions.

Do not stop using Mysoline suddenly, even if you feel fine. Stopping suddenly may cause increased seizures. Follow your doctor's instructions about tapering your dose.

It may take several weeks before you receive the full benefit of taking Mysoline. Your doctor will determine how long to treat you with this medicine.

If you use this medicine long-term, you may need frequent medical tests.

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

In case of emergency, wear or carry medical identification to let others know you take seizure medication.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Mysoline?

Avoid driving or hazardous activity until you know how Mysoline will affect you. Your reactions could be impaired.

Drinking alcohol with this medicine can increase side effects.

Mysoline side effects

Get emergency medical help if you have signs of an allergic reaction: hives, mouth sores, skin rash with blistering and peeling; difficult breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, 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:

  • unusual thoughts or behavior;

  • loss of balance or coordination;

  • fever, chills, sore throat;

  • easy bruising or bleeding; or

  • pale skin, unusual tiredness.

Common side effects may include:

  • dizziness, drowsiness, spinning sensation;

  • problems with balance or muscle movement;

  • nausea, vomiting, loss of appetite;

  • feeling tired or irritable;

  • blurred vision;

  • rash; or

  • impotence, sexual problems.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Mysoline?

Using Mysoline with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Other drugs may affect Mysoline, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

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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