Overview
Phenytoin is classified as a hydantoin derivative and despite its narrow therapeutic index, it is one of the most commonly used anticonvulsants. Since it's introduction about 80 years ago, phenytoin has not only been established as an effective anti-epileptic, but has also been investigated for several other indications such as bipolar disorder, retina protection, and wound healing. Clinicians are advised to initiate therapeutic drug monitoring in patients who require phenytoin since even small deviations from the recommended therapeutic range can lead to suboptimal treatment, or adverse effects. Both parenteral and oral formulations of phenytoin are available on the market.
Indication
Phenytoin is indicated to treat grand mal seizures, complex partial seizures, and to prevent and treat seizures during or following neurosurgery. Injectable phenytoin and Fosphenytoin, which is the phosphate ester prodrug formulation of phenytoin, are indicated to treat tonic-clonic status epilepticus, and for the prevention and treatment of seizures occurring during neurosurgery.
Associated Conditions
- Complex Partial Seizure Disorder
- Generalized Tonic-Clonic Seizures
- Grand Mal Status Epilepticus
- Jacksonian epilepsy
- Partial-Onset Seizures
- Petit Mal Epilepsy
- Seizure Disorder, Post Traumatic
- Seizures
- Status; Epilepticus, Tonic-clonic
- Temporal Lobe Epilepsy (TLE)
- Convulsive disorders
Clinical Trials
Title | Posted | Study ID | Phase | Status | Sponsor |
|---|---|---|---|---|---|
2025/07/18 | Not Applicable | Not yet recruiting | All India Institute of Medical Sciences, Jodhpur | ||
2025/07/15 | Not Applicable | Not yet recruiting | |||
2025/04/09 | Phase 1 | Recruiting | |||
2025/04/02 | Phase 1 | Recruiting | |||
2025/04/01 | Phase 1 | Completed | |||
2024/12/06 | Phase 1 | Completed | |||
2024/10/09 | Phase 1 | Completed | |||
2024/08/07 | Phase 1 | Completed | |||
2024/06/20 | Phase 1 | Completed | |||
2024/04/23 | Phase 1 | Recruiting |
FDA Drug Approvals
Approved Product | Manufacturer | NDC Code | Route | Strength | Effective Date |
|---|---|---|---|---|---|
| REMEDYREPACK INC. | 70518-0841 | ORAL | 50 mg in 1 1 | 2/13/2024 | |
| Aurobindo Pharma Limited | 65862-692 | ORAL | 100 mg in 1 1 | 9/21/2023 | |
| Taro Pharmaceuticals U.S.A., Inc | 51672-4146 | ORAL | 50 mg in 1 1 | 6/28/2022 | |
| Golden State Medical Supply, Inc. | 51407-982 | ORAL | 100 mg in 1 1 | 5/27/2025 | |
| REMEDYREPACK INC. | 70518-1776 | ORAL | 100 mg in 1 1 | 2/22/2024 | |
| Parke-Davis Div of Pfizer Inc | 0071-0007 | ORAL | 50 mg in 1 1 | 3/21/2022 | |
| Hikma Pharmaceuticals USA Inc. | 0641-0493 | INTRAMUSCULAR, INTRAVENOUS | 50 mg in 1 mL | 1/18/2024 | |
| Major Pharmaceuticals | 0904-6187 | ORAL | 100 mg in 1 1 | 4/1/2024 | |
| Aphena Pharma Solutions - Tennessee, LLC | 71610-479 | ORAL | 100 mg in 1 1 | 11/12/2020 | |
| American Health Packaging | 60687-275 | ORAL | 125 mg in 5 mL | 10/31/2022 |
EMA Drug Approvals
Approved Product | Authorization Holder | Status | Issued Date |
|---|---|---|---|
| No EMA approvals found for this drug. | |||
HSA Drug Approvals
Approved Product | Manufacturer | Approval Number | Dosage Form | Strength | Approval Date |
|---|---|---|---|---|---|
| DILANTIN CAPSULE 100 mg | SIN09208P | CAPSULE | 100 mg | 2/25/1997 | |
| DBL PHENYTOIN INJECTION BP 50 mg/ml | SIN08183P | INJECTION | 50 mg/ml | 5/22/1995 | |
| Dilantin 125® (Phenytoin Oral Suspension, USP) 125mg/5ml | SIN13114P | SUSPENSION | 125.00mg/5ml | 6/6/2005 | |
| DILANTIN CAPSULE 30 mg | SIN06056P | CAPSULE | 30 mg | 5/22/1991 | |
| PHARMANIAGA PHENYTOIN SODIUM SOLUTION FOR INJECTION 250MG/5ML | SIN16560P | INJECTION, SOLUTION | 250mg/5mL | 8/2/2022 |
NMPA Drug Approvals
Approved Product | Company | Approval Number | Drug Type | Dosage Form | Approval Date |
|---|---|---|---|---|---|
| Phenytoin Sodium Tablets | 国药准字H44020161 | 化学药品 | 片剂 | 4/3/2020 | |
| Phenytoin Sodium Tablets | 国药准字H23022476 | 化学药品 | 片剂(素片) | 7/27/2020 | |
| Phenytoin Sodium Tablets | 国药准字H51021834 | 化学药品 | 片剂(薄膜衣) | 4/24/2020 | |
| Phenytoin Sodium Tablets | 国药准字H53021426 | 化学药品 | 片剂 | 7/29/2020 | |
| Phenytoin Sodium Tablets | 国药准字H32022551 | 化学药品 | 片剂 | 6/23/2020 | |
| Phenytoin Sodium Tablets | 国药准字H22023362 | 化学药品 | 片剂 | 4/10/2020 | |
| Phenytoin Sodium Tablets | 国药准字H41020002 | 化学药品 | 片剂 | 6/24/2020 | |
| Phenytoin Sodium Tablets | 国药准字H23022003 | 化学药品 | 片剂 | 7/8/2020 | |
| Phenytoin Sodium Tablets | 国药准字H13021694 | 化学药品 | 片剂 | 6/1/2020 | |
| Phenytoin Sodium Tablets | 国药准字H14020187 | 化学药品 | 片剂 | 8/17/2020 |
PPB Drug Approvals
Approved Product | Registration No. | Company | Licence No. | Strength | Registration Date |
|---|---|---|---|---|---|
| No PPB approvals found for this drug. | |||||
TGA Drug Approvals
Approved Product | ARTG ID | Sponsor | Registration Type | Status | Registration Date |
|---|---|---|---|---|---|
| PHENYTOIN JUNO (phenytoin sodium) 250mg/ 5mL injection ampoule | 117865 | Medicine | A | 12/22/2006 | |
| DBL PHENYTOIN INJECTION 250mg/5mL ampoule | 46943 | Medicine | A | 11/30/1993 | |
| DILANTIN PAEDIATRIC SUSPENSION phenytoin 30mg/5mL oral liquid bottle | 14309 | Medicine | A | 9/20/1991 | |
| DILANTIN phenytoin sodium 100 mg capsule bottle | 295265 | Medicine | A | 12/11/2017 | |
| DBL PHENYTOIN INJECTION 100mg/2mL ampoule | 46942 | Medicine | A | 11/30/1993 | |
| PHENYTOIN JUNO (phenytoin sodium) 100mg/ 2mL injection ampoule | 117872 | Medicine | A | 12/22/2006 | |
| DILATIN phenytoin sodium 30 mg capsule bottle | 295264 | Medicine | A | 12/11/2017 | |
| DILANTIN INFATABS 50 mg chewable tablet bottle | 297268 | Medicine | A | 7/31/2018 |
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