Fosphenytoin Sodium

FOSPHENYTOIN

Manufacturer: Amneal Pharmaceuticals LLC

Score: 141.0

Quick Summary

Fosphenytoin sodium injection is indicated for the treatment of generalized tonic-clonic status epilepticus and prevention and treatment of seizures occurring during neurosurgery. It is a prodrug of phenytoin, and its anticonvulsant effects are attributable to phenytoin. The recommended dosage is 15-20 mg PE/kg at a rate of 100-150 mg PE/min for adult status epilepticus and 10-20 mg PE/kg for non-emergent loading and maintenance dosing. Important safety information includes the risk of severe hypotension and cardiac arrhythmias, especially with rapid infusion rates. Contraindications include hypersensitivity to fosphenytoin or phenytoin, sinus bradycardia, and prior acute hepatotoxicity. Special population considerations include use during pregnancy, pediatric and geriatric use.

Key Clinical Findings and Indications

Treatment of generalized tonic-clonic status epilepticus
Prevention and treatment of seizures occurring during neurosurgery
Substitution for oral phenytoin when oral administration is not possible

Important Safety Information

Warning

Cardiovascular risk associated with rapid infusion rates

Contraindications

Hypersensitivity to fosphenytoin or phenytoin
Sinus bradycardia
Prior acute hepatotoxicity
Co-administration with delavirdine

Adverse Reactions

Severe hypotension and cardiac arrhythmias
Nystagmus
Dizziness
Somnolence
Ataxia

Dosing Recommendations

General Guidance

Dose adjustments may be necessary in patients with renal or hepatic impairment, or in those with hypoalbuminemia

Status epilepticus

Adult Dose

15-20 mg PE/kg at a rate of 100-150 mg PE/min

Pediatric Dose

15-20 mg PE/kg at a rate of 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower)

Non-emergent loading and maintenance dosing

Adult Dose

10-20 mg PE/kg

Pediatric Dose

10-15 mg PE/kg at a rate of 1-2 mg PE/kg/min (or 150 mg PE/min, whichever is slower)

Special Population Considerations

Pregnancy

Prenatal exposure to phenytoin may increase the risk of congenital malformations and other adverse developmental outcomes
Periodic measurement of serum phenytoin concentrations is recommended during pregnancy

Nursing Mothers

Pediatric Use

Fosphenytoin sodium is indicated for the treatment of generalized tonic-clonic status epilepticus and prevention and treatment of seizures occurring during neurosurgery in all pediatric age groups
The rate of administration should not exceed 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower) in pediatric patients

Geriatric Use

No systematic studies in geriatric patients have been conducted
Lower or less frequent dosing may be required due to decreased phenytoin clearance with increasing age