PHENYTOIN
Phenytoin is an anti-epileptic agent indicated for the management of specific seizure types and for seizure control in surgical settings. It is used to treat generalized tonic-clonic and complex partial seizures. Additionally, the medication is administered to prevent and treat seizures that occur during or after neurosurgical procedures.
How PHENYTOIN Works
While the exact therapeutic mechanism of phenytoin is not fully established, it is believed to function through the voltage-dependent blockade of membrane sodium channels. By targeting these channels, the drug reduces sustained high-frequency neuronal discharges in the brain. This stabilization of neuronal activity helps manage and prevent seizure activity.
Details
- Status
- Discontinued
- First Approved
- 1992-09-25
- Routes
- ORAL
- Dosage Forms
- SUSPENSION, TABLET, CHEWABLE
PHENYTOIN Approval History
What PHENYTOIN Treats
3 indicationsPHENYTOIN is approved for 3 conditions since its original approval in 1992. These indications span multiple therapeutic areas including oncology, immunology, and more.
- Generalized Tonic-Clonic Seizures
- Complex Partial Seizures
- Seizures
PHENYTOIN Competitive Set
ProThree rings of competition based on shared molecular targets and treated indications.
Direct competitors
Same target(s) AND same indication — head-to-head.
MoA expansion candidates
Same target(s), different indications — where else is this mechanism being explored?
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 PHENYTOIN
3 of 20FDA-approved drugs for similar conditions. Compare mechanisms and indications to understand treatment alternatives.
Clinical Trial Registry
23 trials| Trial | Sponsor ID | Phase | Status | Title |
|---|---|---|---|---|
| NCT07066722 | 219890 | Ph 1 | completed | A Study to Evaluate VH4524184 Tablet Absorption, Effects of Food, and Interactions With Other Drugs in Healthy Adults |
| NCT06719557 | 1084-008 MK-1084-008, CA43207 | Ph 1 | completed | A Study of the Effect of Itraconazole and Phenytoin on Calderasib (MK-1084) in Healthy Adults (MK-1084-008) |
| NCT06906809 | BGB-16673-105 | Ph 1 | completed | Effect of Phenytoin or Itraconazole on How BGB-16673 is Absorbed and Removed From the Body in Healthy Participants |
| NCT06919991 | ARC-29 | Ph 1 | completed | Drug-Drug Interaction Study of Casdatifan in Healthy Adult Participants (ARC-29) |
| NCT07072624 E-PTS | AIIMS/IEC/2024/4889 IIRPIG-2023-0001210 | Ph 4 | recruiting | Early Post-Traumatic Seizures Prevention Trial (E-PTS Trial) |
| NCT06903715 | 6482-035 CA46602 | Ph 1 | completed | A Clinical Study of Belzutifan (MK-6482) Alone or With Phenytoin in Healthy Participants (CA46602/MK-6482-035) |
| NCT06543043 | BGB-11417-107 QSC302214 | Ph 1 | completed | A Study to Evaluate the Effects of Phenytoin and Itraconazole on Sonrotoclax (BGB-11417) in Healthy Volunteers |
| NCT04845646 | ASC41-105 | Ph 1 | completed | DDI Study of ASC41 in HV and the PK, Safety and Tolerability in Subjects With NAFLD. |
| NCT05901714 | IM026-026 | Ph 1 | completed | A Study to Assess the Effect of Phenytoin on the Drug Levels of Afimetoran and the Effect of Afimetoran on the Drug Levels of Midazolam |
| NCT05637086 | 22.09.108 | Ph 2 | recruiting | Clinical Study Evaluating Safety of Pentoxifylline and Celecoxib in Patients With Grand-Mal Epilepsy Treated by Phenytoin Monotherapy |
| NCT05995249 | TAK-279-1002 | Ph 1 | completed | A Study of the Interaction of TAK-279 With Substances That Have an Impact on Metabolism in Healthy Adults |
| NCT01478035 | INFSNC1 | Ph 4 | terminated | Study on the Efficacy of Phenytoin in the Prophylaxis of Seizures of Patients With Pneumococcal Meningitis at Least 50 Yrs Old. |
| NCT01730313 | CDC-CGH-6318 | Ph 2 | withdrawn | Treatment of Nodding Syndrome - A Randomized Blinded Placebo-Controlled Crossover Trial of Oral Pyridoxine and Conventional Anti-Epileptic Therapy, in Northern Uganda - 2012 |
| NCT04981704 | SPI-POZ-103 | Ph 1 | completed | A Study to Evaluate the Effect of Multiple Doses of Itraconazole, Phenytoin, and Paroxetine on the Single-Dose Pharmacokinetics of Poziotinib in Healthy Adult Participants |
| NCT01122953 | A4121009 | Ph 1 | completed | Bioequivalence Study Of PHENYTOIN Suspension Made By Pfizer, Versus EPAMIN® Made By McNeil LA LLC In Healthy Volunteers Under Fasting Conditions |
| NCT01187719 VITA 2 | UMCN-AKF 09.02 | Ph 2 | completed | The Effect of Phenytoin on the Pharmacokinetics of Nevirapine and the Development of Nevirapine Resistance |
| NCT02939937 results posted | 9411257013 | Ph 2 | completed | Effect of Phenytoin on the Ganglion Cell Layer in Patients With Optic Neuritis |
| NCT02374567 GAP | GAP-2014 | Ph 3 | terminated | Pharmacovigilance in Gerontopsychiatric Patients |
| NCT00627575 | LEP108937 | Ph 1 | completed | AED/Statin Interaction Study |
| NCT02409433 | 100739 | Ph 4 | terminated | Comparative Trial of IV Lacosamide Versus Phenytoin for Seizure Management |
| NCT01451593 | UCL/11/0083 | Ph 2 | completed | Neuroprotection With Phenytoin in Optic Neuritis |
| NCT01635829 | CR100830 VX-950HPC1002, 2012-001411-23 | Ph 1 | completed | A Study to Investigate the Potential Pharmacokinetic Interactions Between Phenytoin or Carbamazepine and Telaprevir |
| NCT07590102 | BGB-58067-102 | Ph 1 | not yet recruiting | A Study to Investigate the Effect of the CYP3A Inducer Phenytoin and the CYP3A Inhibitor Itraconazole on the Pharmacokinetics of BGB-58067 in Healthy Participants |
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.
PHENYTOIN FDA Label Details
Indications & Usage
PHENYTOIN is indicated for the treatment of Generalized Tonic-Clonic Seizures; Complex Partial Seizures; Seizures.
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Full clinical data, patents, trials, and competitive landscape for phenytoin.
Data Sources
Data sourced from official FDA and NIH databases. Click links to verify on original sources.