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ethosuximide

Generic Name: ethosuximide (ETH oh SUX i mide)
Brand Name: Zarontin

What is ethosuximide?

Ethosuximide is an anti-epileptic medication, also called an anticonvulsant.

Ethosuximide is used alone or in combination with other medications to treat absence seizures (also called "petit mal" seizures) in adults and children.

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

What is the most important information I should know about ethosuximide?

Do not stop using ethosuximide suddenly. Stopping suddenly may cause increased seizures.

What should I discuss with my healthcare provider before taking ethosuximide?

You should not use this medicine if you are allergic to ethosuximide or to other seizure medications.

To make sure ethosuximide is safe for you, tell your doctor if you have:

  • lupus;

  • liver disease;

  • kidney disease; or

  • a history of depression, mood problems, or suicidal thoughts or actions.

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

Follow your doctor's instructions about taking seizure medication if you are pregnant. Do not start or stop taking this medicine without your doctor's advice, and tell your doctor right away if you become pregnant. Ethosuximide may cause harm to an unborn baby, but having a seizure during pregnancy could harm both mother and baby. The benefit of preventing seizures may outweigh any risks to the baby.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of ethosuximide on the baby.

Ethosuximide can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Ethosuximide should not be given to a child younger than 3 years old.

How should I take ethosuximide?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

While using ethosuximide, you may need frequent blood tests. Your kidney function may also need to be checked.

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

Call your doctor if your seizures get worse or you have them more often while taking ethosuximide.

Wear a medical alert tag or carry an ID card stating that you take ethosuximide. Any medical care provider who treats you should know that you take seizure medication.

Use ethosuximide regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

Store at room temperature away from moisture and heat. Do not allow liquid medicine to freeze.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

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

Overdose symptoms may include nausea, vomiting, extreme drowsiness, and weak or shallow breathing.

What should I avoid while taking ethosuximide?

Drinking alcohol with this medicine can cause side effects.

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Ethosuximide side effects

Get emergency medical help if you have signs of an allergic reaction: hives; 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, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), depressed, or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have:

  • fever, chills, flu symptoms, sore throat, feeling very weak;

  • confusion, hallucinations, unusual thoughts or behavior, extreme fear;

  • worsening seizures;

  • lupus-like syndrome--joint pain or swelling with fever, swollen glands, muscle aches, chest pain, vomiting, unusual thoughts or behavior, and patchy skin color;

  • signs of inflammation in your body--swollen glands, flu symptoms, easy bruising or bleeding, severe tingling or numbness, muscle weakness, upper stomach pain, jaundice (yellowing of the skin or eyes), chest pain, new or worsening cough, trouble breathing; or

  • severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

  • upset stomach, nausea, stomach pain, loss of appetite;

  • diarrhea, weight loss;

  • hiccups;

  • swelling in your tongue or gums;

  • headache, dizziness, trouble concentrating; or

  • feeling tired.

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.

See also: Side effects (in more detail)

Ethosuximide dosing information

Usual Adult Dose for Seizures:

Initial dose: 500 mg (10 mL) orally daily
Maintenance dose: Dosage may be increased by small increments, for example 250 mg daily every 4 to 7 days, until optimal seizure control with minimal side effects is achieved. Dosages greater than 1.5 g per day, in divided doses, should be administered only under strict supervision of a physician.

Usual Pediatric Dose for Seizures:

3 to 6 years:
Initial dose: 250 mg (5 mL) orally daily
Maintenance dose: Dosage may be increased by small increments, for example 250 mg daily every 4 to 7 days, until optimal seizure control with minimal side effects is achieved. For most pediatric patients the optimal dose is 20 mg/kg/day in divided doses. Dosages greater than 1.5 g per day, in divided doses, should be administered only under close supervision by a physician.

> 6 to 18 years:
Initial dose: 500 mg (10 mL) orally daily
Maintenance dose: Dosage may be increased by small increments, for example 250 mg daily every 4 to 7 days, until optimal seizure control with minimal side effects is achieved. For most pediatric patients the optimal dose is 20 mg/kg/day in divided doses. Dosages greater than 1.5 g per day, in divided doses, should be administered only under close supervision by a physician.

What other drugs will affect ethosuximide?

Taking this medicine with other drugs that make you dizzy or sleepy can worsen this effect. Ask your doctor before taking ethosuximide with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Tell your doctor about all your current seizure medications, and any you start or stop using.

Other drugs may interact with ethosuximide, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about ethosuximide.
  • 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.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 8.01. Revision Date: 2016-07-25, 4:21:26 PM.

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