Maximum Daily Dose of Buspirone (BuSpar)
The maximum recommended daily dose of buspirone (BuSpar) is 60 mg per day, typically administered as 20 mg three times daily. 1
Dosing Guidelines
- Initial dosage should start at 5 mg twice daily 1
- Dose can be gradually increased based on clinical response and tolerability 1
- Most patients are successfully managed on daily doses ranging from 15 to 30 mg/day 2
- Higher doses up to 60 mg daily (20 mg three times daily) may be required for optimal therapeutic effect in some patients 1
- Buspirone has a short half-life of approximately 2.5 hours, which typically requires divided dosing throughout the day 3
Clinical Considerations
- Buspirone may take 2 to 4 weeks to become effective for anxiety symptoms 1
- The medication is most useful for patients with mild to moderate agitation or anxiety 1
- Buspirone shows linear pharmacokinetics over the dose range of 10 to 40 mg 3
- When used for anxiety disorders, buspirone has been safely administered for periods up to one year 2
Special Populations
- Patients with hepatic impairment may require lower doses due to significantly higher drug exposure (15-fold higher) and doubled half-life compared to healthy individuals 3
- Patients with renal impairment may also require dose adjustment as drug exposure can be twice that of healthy individuals 3
- Food can increase buspirone bioavailability by approximately 2-fold, so consistent administration with respect to meals is recommended 3
Drug Interactions
- Concomitant use with CYP3A4 inhibitors (verapamil, diltiazem, erythromycin, itraconazole) can substantially increase buspirone plasma concentrations, potentially requiring dose reduction 3
- CYP3A4 inducers like rifampicin can decrease buspirone plasma concentrations by approximately 10-fold, potentially requiring dose increases 3
Clinical Efficacy at Higher Doses
- In some studies, buspirone has been used safely at doses up to 90 mg/day for major depression with moderate anxiety 4
- For posttraumatic stress disorder, final maximum dosages ranging from 35-60 mg daily have been reported effective 5
Safety Considerations
- Buspirone does not typically cause significant sedation, psychomotor impairment, or dependence compared to benzodiazepines 6
- Common side effects at higher doses include nausea, dizziness, headache, and nervousness 2, 6
- Unlike benzodiazepines, abrupt discontinuation of buspirone after long-term use has not been associated with withdrawal symptoms 2
When prescribing buspirone, it's important to recognize that while the maximum recommended dose is 60 mg daily, most patients achieve therapeutic benefit at lower doses (15-30 mg daily), and dose adjustments should be made gradually to minimize side effects while maximizing clinical benefit.