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Ethosuximide (By mouth)

Ethosuximide (eth-oh-SUX-i-mide)

Treats absence (petit mal) seizures.

Brand Name(s):

Zarontin

When This Medicine Should Not Be Used:

How to Use This Medicine:

Liquid Filled Capsule, Liquid

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• This medicine can be used with other seizure medicines. Keep using all of your seizure medicines unless your doctor tells you to stop.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Do not freeze the oral liquid.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some foods and medicines can affect how ethosuximide works. Tell your doctor knows if you using phenytoin or valproic acid.
• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Tell your doctor knows if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, blood or bone marrow problems, lupus, or a history of depression or mental health problems.
• This medicine may cause the following problems:
  • Lupus
  • Unusual thoughts or behavior (including depression, thoughts of suicide)
  • Serious skin reactions, including Stevens-Johnson syndrome
  • Drug reaction with eosinophilia and systemic symptoms (DRESS), which can be life-threatening
• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
• This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.
• Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely. Your seizures may return or occur more often if you stop this medicine suddenly.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Blistering, peeling, red skin rash
• Depression, unusual changes in mood or behavior, thoughts of hurting yourself
• Fever, chills, cough, sore throat, body aches
• Problems with balance or walking, blurred vision, headache
• Swollen glands in your armpits, neck, or groin, chest pain, trouble breathing
• Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

• Diarrhea, nausea, vomiting, loss of appetite, stomach pain
• Dizziness, drowsiness
• Weight loss

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024