Phenobarbital
Generic Details
Generic Name
Phenobarbital
Other Names
- Luminal
Drug Class
- Barbiturate
Chemical Formula
C₁₂H₁₂N₂O₃
Molecular Weight
232.235 g/mol
Mechanism of Action
- Enhances the activity of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA)
Indications
- Seizure disorders
- Anxiety
- Insomnia
Common Dosage Forms
- Tablet
- Elixir
- Injection
Typical Dosage
- Adult: 60-200 mg per day
- Child: 3-6 mg/kg/day
Pediatric Dosage
- 2-6 mg/kg/day
Geriatric Dosage
- Lower doses may be required due to decreased metabolism and clearance
Side Effects
- Drowsiness
- Dizziness
- Confusion
- Nausea
- Rash
Contraindications
- Hypersensitivity to barbiturates
- Porphyria
Pregnancy Category
- D
Lactation Safety
- L4 - Limited Data - Breastfeeding Not Recommended
Drug Interactions
- Alcohol
- CNS depressants
- Anticoagulants
Overdose Symptoms
- Respiratory depression
- Coma
- Hypotension
Antidote for Overdose
- Activated charcoal
- Maintain airway and ventilation
Storage Conditions
- Store at room temperature away from light and moisture
Pharmacokinetics
- Absorption: Rapidly absorbed from the gastrointestinal tract
- Distribution: Widely distributed throughout the body, including the CNS
- Metabolism: Hepatic metabolism
- Excretion: Primarily excreted in the urine
Precautions
- Use with caution in patients with a history of substance abuse or addiction
Warnings
- May cause dependence and tolerance with long-term use