Anti-epileptic Agent
Zarontin
The FDA lists this product in 2 strengths and forms.
Indications
Zarontin is indicated for the control of absence (petit mal) epilepsy.
Contraindications
Ethosuximide should not be used in patients with a history of hypersensitivity to succinimides.
Warnings and precautions
Blood Dyscrasias: Blood dyscrasias, including some with fatal outcome, 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. Drug-Induced Immune Thrombocytopenia: Drug-induced immune thrombocytopenia (DITP) has been reported with ethosuximide.
In the reported cases, the onset of symptoms occurred 1 to 3 weeks after initiation of ethosuximide; one patient had recurrence of symptoms within 1 day of a subsequent re-challenge with the drug. In those cases in which the platelet count was specified, the nadir was 2,000 and 3,000/mm 3 . When DITP is suspected, discontinue Zarontin, monitor serial platelet counts, and treat as appropriate. If possible, assess the presence of drug-dependent antiplatelet antibodies.
Avoid future use of Zarontin in patients with history of ethosuximide-induced DITP. Effects on Liver and Kidneys: Ethosuximide is capable of producing morphological and functional changes in the animal liver. In humans, abnormal liver and renal function studies have been reported. Ethosuximide should be administered with extreme caution to patients with known liver or renal disease. Periodic urinalysis and liver function studies are advised for all patients receiving the drug.
Systemic Lupus Erythematosus: Cases of systemic lupus erythematosus have been reported with the use of ethosuximide. The physician should be alert to this possibility. Suicidal Behavior and Ideation: Antiepileptic drugs (AEDs), including Zarontin, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with any AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior.



