Phenytoin Sodium

Generic Details

Generic Name

Phenytoin Sodium

Other Names

  • Dilantin
  • Eptoin

Drug Class

  • Anti-epileptic
  • Anticonvulsant

Chemical Formula

C15H11N2NaO2

Molecular Weight

274.25 g/mol

Mechanism of Action

  • Blocks voltage-sensitive sodium channels in neuronal membranes

Indications

  • Epilepsy
  • Seizures

Common Dosage Forms

  • Tablet
  • Capsule
  • Oral Suspension

Typical Dosage

  • 100-200mg orally 2-3 times daily

Pediatric Dosage

  • 5mg/kg/day in divided doses

Geriatric Dosage

  • Lower initial doses may be needed for elderly patients

Side Effects

  • Dizziness
  • Drowsiness
  • Nausea
  • Confusion
  • Gingival hyperplasia

Contraindications

  • Hypersensitivity to phenytoin
  • Heart block

Pregnancy Category

  • D

Lactation Safety

  • Caution advised

Drug Interactions

  • Warfarin
  • Oral contraceptives
  • Cimetidine

Overdose Symptoms

  • Nystagmus
  • Ataxia
  • Mental confusion

Antidote for Overdose

  • Activated charcoal
  • Supportive measures

Storage Conditions

  • Store at room temperature away from light and moisture

Pharmacokinetics

  • Absorption: Well absorbed after oral administration
  • Distribution: Highly bound to plasma proteins
  • Metabolism: Primarily hepatic
  • Excretion: Primarily renal

Precautions

  • Monitor serum levels regularly
  • Avoid abrupt withdrawal

Warnings

  • Risk of severe dermatological reactions
  • May cause fetal harm during pregnancy

Others

  • May require dosage adjustments in patients with hepatic dysfunction