What is this medicine?
PRIMIDONE (PRI mi done) is a barbiturate. This medicine is used to control seizures in certain types of epilepsy. It is not for use in absence (petit mal) seizures.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Mysoline
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- kidney disease
- liver disease
- suicidal thoughts, plans, or attempt; a previous suicide attempt by you or a family member
- an unusual or allergic reaction to primidone, phenobarbital, other barbiturates or seizure medications, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medicine more often than directed. Do not stop taking except on the advice of your doctor or health care professional.
A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.
Contact your pediatrician or health care professional regarding the use of this medication in children. Special care may be needed. While this drug may be prescribed for children for selected conditions, precautions do apply.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
Do not take this medicine with any of the following medications:
This medicine may also interact with the following medications:
- cancer-treating medications
- female hormones, including contraceptive or birth control pills
- medicines for mental depression, anxiety or other mood problems
- medicines for treating HIV infection or AIDS
- prescription pain medications
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Visit your doctor or health care professional for regular checks on your progress. It may be 2 to 3 weeks before you see the full effects of this medicine. Do not suddenly stop taking this medicine, you may increase the risk of seizures. Your doctor or health care professional may want to gradually reduce the dose. Wear a medical identification bracelet or chain to say you have epilepsy, and carry a card that lists all your medications.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.
Birth control pills may not work properly while you are taking this medicine. Talk to your doctor about using an extra method of birth control.
The use of this medicine may increase the chance of suicidal thoughts or actions. Pay special attention to how you are responding while on this medicine. Any worsening of mood, or thoughts of suicide or dying should be reported to your health care professional right away.
Women who become pregnant while using this medicine may enroll in the North American Antiepileptic Drug Pregnancy Registry by calling 1-888-233-2334. This registry collects information about the safety of antiepileptic drug use during pregnancy.
This medicine may cause a decrease in vitamin D and folic acid. You should make sure that you get enough vitamins while you are taking this medicine. Discuss the foods you eat and the vitamins you take with your health care professional.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- blurred, double vision, or uncontrollable rolling or movements of the eyes
- redness, blistering, peeling or loosening of the skin, including inside the mouth
- shortness of breath or difficulty breathing
- unusual excitement or restlessness, more likely in children and the elderly
- unusually weak or tired
- worsening of mood, thoughts or actions of suicide or dying
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- clumsiness, unsteadiness, or a hang-over effect
- decreased sexual ability
- dizziness, drowsiness
- loss of appetite
- nausea or vomiting
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medicine?
Keep out of the reach of children.
This medicine may cause accidental overdose and death if it taken by other adults, children, or pets. Mix any unused medicine with a substance like cat litter or coffee grounds. Then throw the medicine away in a sealed container like a sealed bag or a coffee can with a lid. Do not use the medicine after the expiration date.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F).
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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