Phenobarbital

Category: pharmacological

Aliases: Luminal

Pharmacological Mechanism

Long-acting barbiturate — GABA-A receptor positive allosteric modulator (binds different site than benzodiazepines). Anticonvulsant + sedative. Strong CYP3A4 / CYP2B6 / UGT inducer — major DDI source. Largely replaced by safer antiseizure agents but still used in resource-limited settings + neonatal seizures.

Half-Life (t½)

PO: 96h, IV: 96h, IM: 96h

Dosing Guidelines

• PO: Typical 100mg (Range: 30 - 300 mg)

Target Organ Systems

• nervous
• digestive

Interactions

• Theophylline