Brand Names: Zarontin, generics
Ethosuximide (ETH oh SUX i mide) has been approved by the FDA to control absence (petit mal) epilepsy.
Your epilepsy treatment should always be discussed with your healthcare provider before use. Based on their judgment and knowledge, a drug may be prescribed for other epilepsy types not included in the indications. For more information, please see the prescribing information.
Ethosuximide is available as a capsule and an oral solution.
If you have a history of being allergic to succinimides (a chemical class of antiseizure medications that usually end in “-suximide”), then you should not take ethosuximide.
Other considerations may influence whether you should take ethosuximide. Tell your healthcare provider if you:
Do not stop taking ethosuximide suddenly unless directed to do so by your healthcare provider.
As with all antiseizure medications, ethosuximide should be withdrawn gradually to minimize the risk of causing or worsening seizures or status epilepticus. You should not stop using ethosuximide suddenly unless your healthcare provider tells you to stop the medicine because of a serious side effect.
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
Taking ethosuximide with certain other medicines may cause side effects or affect how well they work. Do not start or stop other medicines without talking to your healthcare provider. Especially tell your healthcare provider if you take: drugs that cause sleepiness or dizziness or alcohol.
At this time, there is not enough evidence regarding developmental risks associated with the use of ethosuximide in pregnant people. While ethosuximide crosses the placenta – and cases of birth defects have been reported – data is too limited to know if ethosuximide is the cause of the defects. However, having a seizure during pregnancy could harm both the pregnant individual and the baby. Tell your healthcare provider right away if you become pregnant. Do not start or stop taking seizure medication during pregnancy without your healthcare provider’s advice.
If you become pregnant while taking ethosuximide, talk to your healthcare provider about registering with the North American Antiepileptic Drug (NAAED) Pregnancy Registry. The purpose of this registry is to collect information about the safety of antiseizure medicine during pregnancy. You can enroll in this registry by calling 1-888-233-2334.
Ethosuximide is present in breast milk. It is unknown if there are effects on the breastfed infant, or if ethosuximide impacts milk production. Talk to your healthcare provider about the risks. Your healthcare provider will consider the developmental and health benefits of breastfeeding along with your need for ethosuximide and the potential effect on the infant from ethosuximide or from your epilepsy.
Ethosuximide is approved by the FDA because it is safe and effective for the majority of people who take it. However, there are risks associated with all medicines. Some side effects caused by ethosuximide can be very serious, and even life-threatening. It is important to be informed about these serious reactions and to be aware of their symptoms.
The most common side effects that were reported in studies of ethosuximide are nausea or vomiting indigestion, stomach pain, diarrhea, weight loss, loss of appetite, hiccups, fatigue, dizziness or light-headedness, unsteadiness when walking, headache, and loss of concentration.
Rare but life-threatening reactions involving the immune system or multi-organ hypersensitivity, which can cause serious blood or liver problems have been reported with ethosuximide use. You may or may not have a rash with these types of reactions. Call your healthcare provider right away if you experience fever, frequent infections, severe muscle pain, swelling of your face, eyes, lips, or tongue, swollen lymph glands, unusual bruising or bleeding, weakness, fatigue, yellowing of your skin, or the white part of your eyes, trouble walking or seeing, seizures happening more often, or pain/tenderness in the area toward the top of your stomach (enlarged liver/spleen).
Serious dermatologic reactions, including Stevens-Johnson syndrome (SJS), have been reported with ethosuximide treatment. SJS can be fatal. The onset of symptoms is usually within 28 days, but they can occur later. Ethosuximide should be discontinued at the first sign of a rash unless the rash is clearly not drug-related. If signs or symptoms suggest SJS, use of this drug should not be resumed and alternative therapy should be considered.
Studies have found that people who take antiseizure medications including ethosuximide may have suicidal thoughts or behaviors, which occur in approximately 1 in 500 patients. If you experience any thoughts or impulses to hurt yourself, you should contact your healthcare provider immediately.
Blood dyscrasias (abnormal blood), including some with fatal outcomes, have been reported to be associated with the use of ethosuximide; therefore, periodic blood counts should be performed. Should signs and/or symptoms of infection (e.g., sore throat, fever) develop, blood counts should be considered at that point.
In human studies taking ethosuximide, abnormal liver and renal function has been reported. Ethosuximide should be administered with extreme caution if you have a known liver or renal disease. Periodic urinalysis and liver function studies are advised for all patients receiving the drug.
Cases of systemic lupus erythematosus, an inflammatory autoimmune disease, have been reported with the use of ethosuximide. The physician should be alert to this possibility. Call your healthcare provider right away if you have any of these symptoms: joint pain and swelling, muscle pain, fatigue, low-grade fever, pain in the chest that is worse with breathing, or unexplained skin rash.