MedicinePOM

Ethosuximide

An anti-seizure medicine used to control absence (petit mal) epilepsy.

Clinical information

Common uses

absence (petit mal) seizures

Common side effects

loss of appetite
stomach upset and nausea
drowsiness
headache
dizziness

Cautions

blood problems (low blood counts) have occurred
serious skin reactions (Stevens-Johnson syndrome) reported
mood or behaviour changes, rarely with suicidal thoughts
do not stop suddenly if it prevents major seizures

Interactions

phenytoin (levels may rise)
valproic acid (can raise or lower ethosuximide levels)

Pregnancy: birth defects reported — do not stop without medical advice

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, ethosuximide solution label, setid 19c924c2-f558-4c78-9277-2d7e0df2f505 (accessed 2026-08-16)

Approved brands & formulations2

Brand name	Dosage form	Strength	Importer	Category
Ethosuximide	Capsule	250 mg	—	POM
Ethosuximide	Oral Liquid	250mg/5ml	—	POM