• Basic Info
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What is ethosuximide?
Ethosuximide is a drug used to control seizures. It works by slowing down impulses in the brain that cause seizures. Ethosuximide is used to treat absence or "petit mal" seizures. Ethosuximide may also be used for purposes other than those listed in this medication guide.

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What is the price of this medication and similar alternatives?

This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.

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What are the possible side effects of ethosuximide?

If you experience any of the following serious side effects, stop taking ethosuximide and seek emergency medical attention:

• an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);

• hallucinations or agitation;

• slurred speech or staggering walk;

• a rash;

• changes in vision;

• easy bruising or bleeding; or

• swollen or tender gums.

Other, less serious side effects may be more likely to occur. Continue to take ethosuximide and talk to your doctor if you experience

• nausea, vomiting, decreased appetite, constipation, or diarrhea;

• mild dizziness or drowsiness;

• tender or swollen glands;

• hiccups;

• lethargy and fatigue;

• irritability;

• euphoria;

• abdominal pain;

• headache;

• muscle twitches;

• increased facial hair;

• swelling of the breasts; or

• insomnia.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

Ethosuximide may cause serious blood problems. Notify your doctor immediately if you develop any of the following symptoms, which may be early signs of potential blood problems: fever, sore throat, rash, sores in the mouth, easy bruising, or red or purple bruising.

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How should I take ethosuximide?
Take ethosuximide exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you. Take each dose of ethosuximide with a full glass of water. Take ethosuximide with food to lessen stomach upset. Measure the liquid form of ethosuximide with a special dose-measuring spoon or a cup not with a regular tablespoon to ensure that you measure the correct amount. If you do not have a dose measuring spoon, ask your pharmacist where you can get one.

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What is the most important information I should know about ethosuximide?
Do not stop taking this medication even if you feel better. It is important to continue taking ethosuximide to prevent seizures from recurring. Do not change the brand, generic formulation, or dosage of this medication without first talking to your doctor. Do not drink alcohol while taking this medication. Alcohol can cause deep sedation or sleepiness when taken with ethosuximide. Use caution when driving, operating machinery, or performing other hazardous activities. Ethosuximide may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed and take only the next regularly scheduled dose. Do not take a double dose of this medication.

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What other drugs will affect ethosuximide?
Ethosuximide may increase the amount of other antiseizure medications in the blood. Such medications include phenytoin (Dilantin), mephenytoin (Mesantoin), and ethotoin (Peganone). These drugs must be monitored if they are used with ethosuximide to prevent the occurrence of dangerous side effects. Ethosuximide may decrease the level of primidone (Mysoline) in the blood, which could lead to a loss of seizure control. Valproic acid (Depakote, Depakene) may increase or decrease ethosuximide levels and must be used with caution.

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Ethosuximide has not been formally assigned to a pregnancy category by the FDA. Ethosuximide has been assigned to pregnancy category C by Briggs et. al. Animal studies have not been reported. There are no controlled data in human pregnancy. An increased risk of congenital malformations have been associated with the use of anticonvulsants (including ethosuximide) in epileptic women during pregnancy. Abnormalities reported with ethosuximide use have included spontaneous hemorrhage in the neonate, patent ductus arteriosus, cleft lip and/or palate, mongoloid facies, short neck, altered palmar crease, an accessory nipple, and hydrocephalus. Anomalies associated with anticonvulsant use in pregnancy included neural tube defects, cleft lips, cleft palates, cardiac defects, and microcephaly. The manufacturer states that ethosuximide should only be administered during pregnancy when there are no alternatives and benefit outweighs risk.

Physicians are encouraged to register patients before fetal outcome is known (e.g., ultrasound, results of amniocentesis, etc) into the Antiepileptic Drug (AED) Pregnancy Registry at 1-888-233-2334 or 1-888-AED-AED4. This is an ongoing study at the Massachusetts General Hospital/Harvard Medical School. This study is designed to monitor the outcomes of pregnant women exposed to antiepileptic drugs in order to determine which therapies are associated with increased risk.

Ethosuximide is excreted into human milk Concentrations found in breast milk are comparable to the maternal serum. The effects in the nursing infant are unknown. Ethosuximide is considered compatible with breast-feeding by the American Academy of Pediatrics.

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Who should NOT use this medication?

• Known hypersensitivity to ethosuximide or other succinimides (e.g., methsuximide, phensuximide [no longer commercially available in the US]).

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What does my medication look like?
Ethosuximide is available with a prescription under the brand name Zarontin. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medicine, especially if it is new to you. Zarontin 250 mg--orange gelatin capsules Zarontin 250 mg per 5 mL (1 teaspoon)--raspberry syrup

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What happens if I overdose?
Seek emergency medical treatment if an overdose is suspected. Symptoms of a ethosuximide overdose include confusion, slurred speech, stumbling or staggering walk, imbalance, drowsiness, unconsciousness, nausea, vomiting, tremor, low blood pressure, and slow breathing.

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What should I discuss with my healthcare provider before taking ethosuximide?
Before taking this medication, tell your doctor if you have kidney disease; or liver disease. You may not be able to take ethosuximide, or you may require a dosage adjustment or special monitoring during treatment if you have either of the conditions listed above. Ethosuximide may cause serious blood problems. Notify your doctor immediately if you develop any of the following symptoms, which may be early signs of potential blood problems: fever, sore throat, rash, sores in the mouth, easy bruising, or red or purple bruising.

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Can I stop taking the medication if I feel better?
As a general rule, you should always take your medications exactly as prescribed and do not change the dosage or stop taking the medication without first discussing it with your healthcare provider.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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