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Phensuximide oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.




This medication is used to treat epilepsy and other seizure disorders.

How To Use

Take this medication by mouth exactly as prescribed. Try to take it at the same time each day so you get into a habit of taking this. This may be taken with food or milk if stomach upset occurs. Do not stop taking this medication or change your dose without first consulting your doctor.

Side Effects

Indigestion, change in appetite, nausea, headache, difficulty sleeping, tiredness or weakness may occur the first several days as your body adjusts to the medication. Mood changes, nervousness, thinning or darkening of fine body hair, hiccups, drowsiness, dizziness, or incoordination may also occur. If any of these effects continue or become bothersome, inform your doctor. Notify your doctor if you develop: easy bruising or bleeding, skin rash, blurred vision, fever, sore throat, excessive drowsiness or dizziness, joint pain, behavior changes, depression, seizures. This medication may cause blood disorders. Laboratory tests will be done periodically to monitor for these effects. This medication may turn your urine pink to dark red in color. Do not be alarmed. This is a temporary effect that will stop when the medication is discontinued. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor if you have: liver problems, kidney disease, blood diseases, any allergies. Since this medication can cause drowsiness, dizziness or blurred vision, use caution operating machinery and limit intake of alcoholic beverages. This medication should be used only if clearly needed during pregnancy. Discuss the risks and benefits with your doctor. Since Since small amounts of this medication are found in breast milk, consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of any over-the-counter or prescription medication you take, especially of: anti-anxiety drugs, antidepressants. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea and vomiting.


Keep all doctor's appointments and scheduled laboratory visits so your condition and response to this medication can be monitored closely. It is recommended to carry medical identification stating you are taking this medication.

Missed Dose

It is important to take each dose as scheduled. If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat and light. Do not store in the bathroom.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).