Buspirone Starting Dose for Adults
The recommended initial dose of buspirone for adults is 7.5 mg twice daily (15 mg total daily dose). 1
Dosing Guidelines
Buspirone dosing follows a specific protocol based on FDA labeling:
- Starting dose: 7.5 mg twice daily (15 mg total daily dose) 1
- Dose titration: May increase by 5 mg per day at intervals of 2-3 days as needed 1
- Maintenance dose: Most patients are effectively managed on 15-30 mg daily 2
- Maximum dose: Should not exceed 60 mg per day 1
Administration Considerations
- Timing: Take buspirone consistently with regard to food (either always with or always without food) 1
- Food effects: Bioavailability increases when taken with food compared to fasting state 1, 3
- Absorption: Buspirone is rapidly absorbed with peak plasma concentration occurring within 1 hour 3
- Bioavailability: Has low absolute bioavailability of approximately 4% 3
Special Populations
- Elderly patients: Can typically use standard adult dosing (mean effective dose of 18 mg/day in elderly studies) 4
- Hepatic impairment: Requires dose reduction as plasma concentrations may be 15-fold higher and half-life doubled compared to healthy individuals 3
- Renal impairment: Consider lower starting doses as Cmax and AUC may be doubled 3
Drug Interactions
- CYP3A4 inhibitors: Dose reduction required when co-administered with potent inhibitors like verapamil, diltiazem, erythromycin, and itraconazole 1, 3
- MAOIs: Allow at least 14 days between discontinuing an MAOI and starting buspirone 1
- Rifampin: May decrease buspirone plasma concentrations by approximately 10-fold 3
Clinical Pearls
- Buspirone has a short half-life of approximately 2.5 hours 3
- Unlike benzodiazepines, buspirone does not cause significant sedation or psychomotor impairment 5
- Therapeutic effects may take 2-4 weeks to become fully apparent, unlike the more immediate effects of benzodiazepines 6
- Common side effects include nausea, dizziness, and headache 5, 4
- No evidence of withdrawal syndrome when discontinued after long-term use 2
Monitoring
- Periodically reevaluate the need for continued therapy, especially for treatment extending beyond several months 2
- Monitor for side effects, particularly during dose titration
Remember that buspirone is not effective for immediate anxiety relief and requires consistent dosing over time to achieve therapeutic benefits.