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Extended Phenytoin Sodium
Extended-release phenytoin sodium blocks voltage-gated sodium channels in the brain to reduce neuronal excitability and prevent seizure propagation.
Extended-release phenytoin sodium blocks voltage-gated sodium channels in the brain to reduce neuronal excitability and prevent seizure propagation. Used for Generalized tonic-clonic seizures, Complex partial (temporal lobe) seizures, Simple partial seizures.
At a glance
| Generic name | Extended Phenytoin Sodium |
|---|---|
| Also known as | Dilantin |
| Sponsor | Bristol-Myers Squibb |
| Drug class | Aromatic antiepileptic drug (hydantoin) |
| Target | Voltage-gated sodium channels |
| Modality | Small molecule |
| Therapeutic area | Neurology |
| Phase | FDA-approved |
Mechanism of action
Phenytoin stabilizes the inactive state of voltage-gated sodium channels, reducing the rate of firing of action potentials in neurons. This decreases the spread of seizure activity across the brain. The extended-release formulation provides sustained drug levels, allowing for once or twice daily dosing compared to immediate-release formulations.
Approved indications
- Generalized tonic-clonic seizures
- Complex partial (temporal lobe) seizures
- Simple partial seizures
- Status epilepticus (parenteral formulation)
Common side effects
- Gingival hyperplasia
- Hirsutism
- Ataxia
- Nystagmus
- Diplopia
- Dizziness
- Rash
- Hepatotoxicity
Key clinical trials
- A Study to Evaluate VH4524184 Tablet Absorption, Effects of Food, and Interactions With Other Drugs in Healthy Adults (PHASE1)
- A Study of the Effect of Itraconazole and Phenytoin on Calderasib (MK-1084) in Healthy Adults (MK-1084-008) (PHASE1)
- Early Post-Traumatic Seizures Prevention Trial (E-PTS Trial) (PHASE4)
- Steady-State Study of Extended Phenytoin Sodium Capsules 100 mg and Dilantin® Kapseals® 100 mg (PHASE1)
- A Study to Test the Pharmacokinetics, Efficacy, and Safety of Brivaracetam in Newborns With Repeated Electroencephalographic Seizures (PHASE3)
- A Study to Assess the Effect of Itraconazole, Phenytoin and Gemfibrozil on the Drug Levels of BMS-986166 in Healthy Participants (PHASE1)
- A Placebo-controlled Study of Efficacy & Safety of 2 Trough-ranges of Everolimus as Adjunctive Therapy in Patients With Tuberous Sclerosis Complex (TSC) & Refractory Partial-onset Seizures (PHASE3)
- Antiepileptic Drugs and Vascular Risk Markers (NA)
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 |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Extended Phenytoin Sodium CI brief — competitive landscape report
- Extended Phenytoin Sodium updates RSS · CI watch RSS
- Bristol-Myers Squibb portfolio CI