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Zarontin (Ethosuximide)
Suppresses paroxysmal three cycle per second spike and wave activity associated with absence seizures.
Zarontin (ethosuximide) is a succinimide antiepileptic indicated for control of absence (petit mal) epilepsy. It works by suppressing spike and wave activity and elevating seizure threshold through motor cortex depression. Contraindicated in patients with succinimide hypersensitivity; requires monitoring of serum levels when used with other antiepileptic drugs due to potential interactions. Periodic serum level determinations recommended during concurrent antiepileptic therapy.
At a glance
| Generic name | Ethosuximide |
|---|---|
| Sponsor | Pfizer |
| Drug class | Succinimide |
| Target | Voltage-dependent T-type calcium channel subunit alpha-1G |
| Modality | Small molecule |
| Therapeutic area | Neuroscience |
| Phase | FDA-approved |
| First approval | 1960 |
Mechanism of action
Ethosuximide suppresses the paroxysmal three cycle per second spike and wave activity associated with lapses of consciousness which is common in absence (petit mal) seizures. The frequency of epileptiform attacks is reduced, apparently by depression of the motor cortex and elevation of the threshold of the central nervous system to convulsive stimuli.
Approved indications
- Absence seizure
Common side effects
- Gastrointestinal symptoms
- Nausea and vomiting
- Anorexia
- Gastric upset
- Abdominal pain
- Diarrhea
- Cramps
- Drowsiness
- Headache
- Dizziness
- Fatigue
- Lethargy
Serious adverse events
- Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)
- Stevens-Johnson syndrome
- Agranulocytosis
- Pancytopenia
- Bone marrow suppression
- Paranoid psychosis
- Suicidal intentions
- Leukopenia
- Thrombocytopenia
- Allergic reaction
Drug interactions
- Phenytoin
- Valproic acid
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
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