Phenobarbitone (Phenobarbital)

Barbiturate for Seizures and Sedation

Indication

Used in status epilepticus, neonatal seizures, sedation, and seizure prophylaxis.

Available Form

Injection 20 mg/ml, oral solution 15 mg/ml, tablets 30 mg, 100 mg.

Dosage

Pediatric (IV/IM/PO): 15–20 mg/kg as loading dose for status epilepticus, then 3–5 mg/kg/day divided BID/TID for maintenance.

Adult: 15–20 mg/kg IV/IM as loading dose, maintenance 1–3 mg/kg/day divided BID/TID.

⚡ Major Side Effects

  • Respiratory depression
  • Excessive sedation, drowsiness
  • Hypotension (IV bolus)
  • Allergic reactions, rash

🚫 Contraindications

  • Severe respiratory insufficiency
  • Severe hepatic impairment
  • Hypersensitivity to barbiturates
  • Porphyria

💧 Compatible Solvent

IV injection can be diluted with 0.9% NaCl or 5% dextrose and should be administered slowly to avoid hypotension.

⚠️ Special Precautions

  • Monitor respiration, blood pressure, and level of consciousness.
  • Use caution in elderly, debilitated, or renal/hepatic impaired patients.
  • Avoid rapid IV injection to prevent hypotension and respiratory depression.
  • Long-term use can cause dependence.