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

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

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

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

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 Zarontin, you may need frequent blood tests. Your kidney function may also need to be checked.

Do not stop using Zarontin 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 Zarontin.

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

Use Zarontin 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.

You should not use Zarontin if you are allergic to Zarontin or to other seizure medications.

To make sure Zarontin 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. Zarontin 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.

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

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.

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.

Drinking alcohol with Zarontin 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.

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.

Zarontin may cause serious side effects. 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 of Zarontin 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.

Taking this medicine with other drugs that make you dizzy or sleepy can worsen this effect. Ask your doctor before taking Zarontin 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.