Buspirone Dosing for Generalized Anxiety Disorder (GAD)
The recommended dosage of buspirone for treating generalized anxiety disorder (GAD) is to start at 5 mg twice daily and gradually titrate to a target dose of 20-30 mg per day in divided doses, with a maximum of 60 mg daily. 1
Initial Dosing and Titration
- Starting dose: 5 mg twice daily
- Titration: Gradually increase dose over several days to weeks
- Target dose: 20-30 mg/day total
- Maximum dose: 60 mg/day
- Administration options:
- Twice daily regimen: 15 mg twice daily (30 mg total)
- Three times daily regimen: 10 mg three times daily (30 mg total)
Both twice daily and three times daily regimens show similar efficacy and safety profiles at the same total daily dose 1, 2, 3.
Onset of Action and Monitoring
- Full therapeutic effect takes 2-4 weeks to manifest 1
- Patients should be informed about this delayed onset to manage expectations
- Assess therapeutic response after 2-4 weeks of treatment
- Monitor for common side effects:
- Dizziness
- Headache
- Nausea
- Nervousness
- Palpitations (slightly more common with twice daily dosing) 2
Special Population Considerations
Elderly Patients
- Start at lower doses and titrate more slowly 1
- Safety profile in elderly patients is similar to younger adults 4
- Buspirone has demonstrated significant anxiolytic effects in elderly patients with GAD 5
Hepatic or Renal Impairment
- Use lower doses and titrate cautiously in mild to moderate impairment 1, 4
- Not recommended for patients with severe hepatic or renal impairment due to increased plasma levels and lengthened half-life 4
Clinical Pearls and Pitfalls
Medication discontinuation: If 5% weight loss is not achieved after 12 weeks at the maximum tolerated dose, consider discontinuing the medication 1
Previous benzodiazepine use: Patients previously treated with benzodiazepines may perceive buspirone as less effective due to the lack of immediate sedative effects 1
Test dose consideration: Consider starting with a subtherapeutic "test" dose as initial adverse effects can include increased anxiety or agitation 1
Drug interactions:
Unique properties: Unlike benzodiazepines, buspirone lacks sedative, muscle relaxant, and anticonvulsant properties, and shows no evidence of dependence, tolerance, or withdrawal syndrome 1, 6
Laboratory test interference: Buspirone may interfere with urinary metanephrine/catecholamine assay and should be discontinued at least 48 hours prior to urine collection for catecholamines 4