Section 19 · Monograph
Buspirone
Reviewed Nov 2026FDA label
BuSparAnxiolytic (azapirone)
- Forms
- Tab: 5, 7.5, 10, 15, 30mg
- Dose
- Anxiety: start 5mg two to three times daily, usual 20-30mg/day, max 60mg/day
- MOA
- 5-HT1A partial agonism
Indications
- Generalized anxiety disorderFDA-labeled
Mechanism of Action
- Partial agonist at serotonin 5-HT1A receptors with minimal sedation, no addiction potential and no muscle-relaxant effect
Full Dosing
Adult / usual
- Start 5mg two to three times daily; increase by 5mg/day every 2-3 days; usual 20-30mg/day; max 60mg/day
- Onset takes 1-2 weeks; not effective as-needed
- Reduce dose with strong CYP3A4 inhibitors; avoid grapefruit juice in large amounts
Contraindications
- MAO inhibitors within 14 days
- Hypersensitivity to buspirone
Drug Interactions
- MAO inhibitors: hypertensive crisis
- Strong CYP3A4 inhibitors (itraconazole, clarithromycin) raise levels; inducers lower levels
- Serotonergic drugs: additive serotonergic effects
Adverse Effects
- Dizziness, nausea, headache
- Nervousness and lightheadedness
- Rare serotonin syndrome and restlessness
- Does not cause dependence
Monitoring Parameters
- Anxiety response over 2 weeks
- Dizziness and falls in older adults
- Drug interactions
Pregnancy & Lactation
- Limited human data; use if benefit justifies risk
- Excreted in milk in animals; use caution