Zarontin (Ethosuximide)

(℞) Prescription Required

    Zarontin (Ethosuximide) Dosage and Side Effects

    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.

    Warnings and Precautions

    ZARONTIN can cause a decrease in many types of blood cells (white cells, red cells, platelets). Call your doctor at once if you have any unusual bleeding, weakness, or any signs of infection, even if these symptoms first occur after you have been using the medication for several months.

    ZARONTIN may also cause liver damage. Call your doctor if you have symptoms such as loss of appetite, stomach pain, or jaundice (yellowing of the skin or eyes).

    You may have thoughts about suicide while taking this medication. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

    Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, anxiety, depression, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

    Do not stop using ZARONTIN without first talking to your doctor, even if you feel fine. You may have increased seizures if you stop using ZARONTIN suddenly. You will need to use less and less before you stop the medication completely.

    Contact 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.

    You should not use this medication if you are allergic to ZARONTIN or to other seizure medications.

    To make sure you can safely take ZARONTIN , tell your doctor if you have any of these other conditions:

    • lupus;
    • liver disease;
    • kidney disease; or
    • a history of depression, mood problems, or suicidal thoughts or actions.

    You may have thoughts about suicide while taking this medication. Tell your doctor if you have new or worsening depression or suicidal thoughts during the first several months of treatment, or whenever your dose is changed.

    Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

    It is not known whether ZARONTIN is harmful to an unborn baby, but having a seizure during pregnancy could harm both mother and baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. Follow your doctor's instructions about taking ZARONTIN while you are pregnant.

    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 ZARONTIN on the baby.

    ZARONTIN passes into breast milk and could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

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

    Side Effects

    Get emergency medical help if you have any of these 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, depression, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

    Call your doctor at once if you have a serious side effect such as:

    • fever, chills, swollen glands, flu symptoms, sore throat, swollen glands, feeling very weak;
    • new or worsening cough with fever, trouble breathing;
    • easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
    • joint pain or swelling with mild fever, muscle aches;
    • chest pain, irregular heart rhythm, feeling short of breath;
    • patchy skin color, red spots, or a butterfly shaped skin rash over your cheeks and nose (worsens in sunlight);
    • skin rash, severe tingling, numbness, pain, muscle weakness;
    • upper stomach pain, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes);
    • confusion, hallucinations, unusual thoughts or behavior, extreme fear;
    • swelling, rapid weight gain, urinating less than usual or not at all;
    • the first sign of any skin rash, no matter how mild;
    • 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; or
    • worsening of seizures.

    Less serious side effects may include:

    • upset stomach, mild nausea, stomach cramps, diarrhea, weight loss;
    • swelling in your tongue or gums;
    • headache, dizziness, drowsiness, feeling tired;
    • lack of balance or coordination; or
    • unusual vaginal bleeding.

    This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

    Interactions with this medication

    Do not drink alcohol. It can increase certain side effects of ZARONTIN.

    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.

    Cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for depression or anxiety can add to sleepiness caused by ZARONTIN. Tell your doctor if you regularly use any of these medicines, or any other seizure medication.

    Before taking ZARONTIN, tell your doctor about all other seizure medications you use, especially:

    • phenobarbital (Solfoton);
    • phenytoin (Dilantin); or
    • valproic acid (Depakene, Stavzor).

    This list is not complete and other drugs may interact with ZARONTIN. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

    Proper Use of this medication

    Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

    Your doctor may occasionally change your dose to make sure you get the best results.

    ZARONTIN can lower blood cells that help your body fight infections. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood may need to be tested often. Your kidney and liver function may also need to be tested. Visit your doctor regularly.

    Call your doctor at once if you have any unusual bleeding, weakness, or any signs of infection, including flu-like symptoms. These symptoms may first develop even after you have been using the medication for several months.

    Do not stop using ZARONTIN without first talking to your doctor, even if you feel fine. You may have increased seizures if you stop using ZARONTIN suddenly. You may need to use less and less before you stop the medication completely.

    Contact 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.

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

    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.

    Other related products

    The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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