What is the initial dose of buspirone (anxiolytic medication) for the treatment of generalized anxiety disorder?

Buspirone Dosing for Generalized Anxiety Disorder

For generalized anxiety disorder, buspirone should be initiated at 5 mg twice daily and gradually titrated to a target dose of 20-30 mg per day in divided doses. 1

Initial Dosing and Titration

• Starting dose: 5 mg twice daily
• Titration: Increase by 5 mg per day at intervals of 2-3 days as needed 1, 2
• Target dose: 20-30 mg per day (divided doses)
• Maximum dose: 60 mg per day 1, 2

The FDA label recommends an initial dose of 15 mg daily (7.5 mg twice daily) 2, but clinical guidelines from the American Academy of Family Physicians recommend starting lower at 5 mg twice daily to minimize initial side effects 1.

Dosing Schedule Options

Both twice-daily and three-times-daily regimens are effective when the total daily dose is equivalent:

• 15 mg twice daily (30 mg total)
• 10 mg three times daily (30 mg total)

Research shows no significant difference in efficacy between these two regimens 3, 4, though the twice-daily schedule may offer better convenience and potentially improve compliance 3.

Important Clinical Considerations

1. Onset of action: Full therapeutic effect takes 2-4 weeks to manifest 1

   • Inform patients about this delayed onset to manage expectations
   • This differs significantly from benzodiazepines, which have immediate effects

2. Administration with food:

   • Take buspirone consistently either always with or always without food
   • Bioavailability increases when taken with food 2

3. Common side effects to monitor:

   • Dizziness, headache, nausea, nervousness, and palpitations 1, 3
   • Palpitations may be more common with twice-daily dosing (5% vs 1%) 3

4. Special populations:

   • Elderly patients: Start at lower doses and titrate more slowly 1
   • Hepatic/renal impairment: Use lower doses and titrate cautiously 1

Clinical Pearls

• Unlike benzodiazepines, buspirone lacks sedative properties and has no evidence of dependence, tolerance, or withdrawal syndrome 1
• Patients previously treated with benzodiazepines may perceive buspirone as less effective due to the absence of immediate sedative effects 1
• Consider starting with a subtherapeutic "test" dose if concerned about initial adverse effects, which can include increased anxiety or agitation 1
• Buspirone is effective for generalized anxiety disorder but not for panic disorder 1
• Long-term studies show that buspirone remains safe and effective for up to one year of treatment 5

When initiating treatment, remember that most patients are successfully managed on daily doses ranging from 15 to 30 mg/day 5, and regular reassessment of the need for continued therapy is recommended.