ZARONTIN (ethosuximide)
Zarontin (ethosuximide) is an antiepileptic medication indicated for the control of absence (petit mal) epilepsy.
How ZARONTIN Works
Ethosuximide exerts its anticonvulsant effect by inhibiting T-type voltage-gated calcium channels in thalamic neurons. By reducing these calcium currents, the drug suppresses the rhythmic 3-Hz spike-and-wave discharges in the thalamocortical pathway that are characteristic of absence seizures.
Development Insights
Details
- Status
- Prescription
- First Approved
- 1960-11-02
- Routes
- ORAL
- Dosage Forms
- SYRUP, CAPSULE
ZARONTIN Approval History
What ZARONTIN Treats
1 indicationsZARONTIN is approved for 1 conditions since its original approval in 1960. These indications span multiple therapeutic areas including oncology, immunology, and more.
- Epilepsy
ZARONTIN Competitive Set
ProThree rings of competition based on shared molecular targets and treated indications.
Indication competitors
Same indication, different mechanism — what else might this patient receive?
Filters applied: drops same-active-ingredient (505(b)(2) reformulations), route-mismatch (topical vs systemic), and cross-therapeutic-area matches in same-indication rings.
Drugs Similar to ZARONTIN
3 of 20FDA-approved drugs for similar conditions. Compare mechanisms and indications to understand treatment alternatives.
Clinical Trial Registry
5 trials| Trial | Sponsor ID | Phase | Status | Title |
|---|---|---|---|---|
| NCT02973542 IBSET | CHU-289 2016-002110-42 | Ph 2 | completed | Ethosuximide to Treat IBS |
| NCT04217733 | Sherief Protocol | Ph 3 | recruiting | Ethosuximide and Pentoxifylline in the Treatment of Abdominal Pain Related to Irritable Bowel Syndrome |
| NCT01278004 CINE-E | CCR3116 | Ph 2 | completed | Chemotherapy Induced Painful Peripheral Neuropathy Ethosuximide (The CIN-E Study) |
| NCT01122381 results posted | B5043-R | Ph 1, Ph 2 | terminated | Comparison of a Drug and Placebo in the Prevention of Migraine Headaches |
| NCT00689585 | GEN#07-062 | Ph 2 | terminated | Safety and Efficacy Study of Ethosuximide for the Treatment of Complex Regional Pain Syndrome (CRPS) |
Active Pipeline
Ongoing clinical trials by development phase
Key Completed Trials
Completed studies with published results, ranked by significance
Trial Timeline
Full development history with FDA approval milestones
Understanding FDA Approval Types
| Count | Type | What it means |
|---|---|---|
| - | ORIG | Original approval - drug first enters market |
| - | SUPPL - Efficacy | New indication (new disease/condition approved) |
| - | SUPPL - Labeling | Label text changes (warnings, dosing updates) |
| - | SUPPL - Manufacturing | Production changes (new facility) |
| - | SUPPL - Chemistry | Formulation changes (new dosage strength) |
Green lines in the timeline show ORIG and Efficacy approvals - the clinically meaningful milestones.
ZARONTIN FDA Label Details
Indications & Usage
FDA Label (PDF)ZARONTIN is indicated for the treatment of Epilepsy.
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Data Sources
Data sourced from official FDA and NIH databases. Click links to verify on original sources.
How We Calculate These Metrics
Trial Activity Stage
Measures the current development activity pattern based on trial phases, status, and trends. Important: This measures R&D activity, not commercial lifecycle.
Trial statuses: "Active" means recruiting or ongoing. "Completed" means reached planned endpoint. "Terminated" means stopped early—often due to safety, efficacy, or business reasons.
- Growth: High proportion of early-phase trials (Phase 1/2), active development
- Expansion: Significant Phase 3 activity, approaching or pursuing approvals
- Mature: Substantial Phase 4 post-marketing studies
- Stable: Mixed phase distribution, steady development
- Declining: Low active trial ratio, reduced R&D investment