Methsuximide Oral (patient information)

# Why this medication is prescribed
Methsuximide is used to treat a type of seizure called absence (petit mal) that cannot be treated with other medications. Methsuximide acts on the brain and nervous system in the treatment of epilepsy.
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

# How this medication should be used
Methsuximide comes as a capsule to take by mouth. It is taken once a day at first, but the dosage may be increased gradually to two to four times a day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take methsuximide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Continue to take methsuximide even if you feel well. Do not stop taking methsuximide without talking to your doctor, especially if you have taken large doses for a long time. Abruptly stopping the drug can cause seizures. Your doctor probably will decrease your dose gradually.

# Special precautions
Before taking methsuximide:
- tell your doctor and pharmacist if you are allergic to methsuximide or any other drugs.
- tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially other seizure medications, doxycycline (Vibramycin), isoniazid (INH), medications for colds or allergies such as chlorpheniramine (Chlor-Trimeton), medications for depression such as amitriptyline (Elavil), oral contraceptives, and vitamins. Methsuximide affects the action of other medications, and many medications can affect the action of methsuximide. Tell your doctor and pharmacist everything you are taking.
- tell your doctor if you have or have ever had kidney or liver disease or a blood disorder.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking methsuximide, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking methsuximide.
- you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how this drug affects you.
- remember that alcohol can add to the drowsiness caused by this drug.
- plan to protect your eyes in the sun. Methsuximide may make your eyes more sensitive to light. *Wear dark glasses in bright light.

# Special dietary instructions
Methsuximide may cause an upset stomach. Take methsuximide with food. Drink plenty of water.

# What to do if you forget a dose
Take the missed dose as soon as you remember it. However, if it is within 4 hours of the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

# Side effects

## Minor side effects
Methsuximide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- drowsiness
- upset stomach
- vomiting
- constipation
- diarrhea
- stomach pain
- loss of taste and appetite
- weight loss
- irritability
- mental confusion
- depression
- insomnia
- nervousness
- headache

## Severe side effects
If you experience any of the following symptoms, call your doctor immediately:
- difficulty coordinating movements
- joint pain
- red, itchy skin rash
- easy bruising
- tiny purple-colored skin spots
- bloody nose
- unusual bleeding
- yellowing of the skin or eyes
- dark urine
- fever
- sore throat
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online  or by phone .

# Storage conditions needed for this medication
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature, away from light, excess heat, and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

# In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

# Other information
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to methsuximide.
Call your doctor if you continue to have seizures or convulsions while taking this medication.
If you give this drug to a child, observe and keep a record of the child's moods, behavior, attention span, hand-eye coordination, and ability to solve problems and perform tasks requiring thought. Ask the child's teacher to keep a similar record. This information can help the child's doctor determine whether to continue the drug or to change the dose or drug.
Wear identification (Medic Alert) indicating medication use and epilepsy.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

# Brand names
- Celontin Kapseals