Maximum Dose for Buspar (Buspirone)
The maximum recommended dose for buspirone is 60 mg per day, typically divided into two or three doses, though doses up to 90 mg per day have been studied and found safe in clinical trials. 1
Standard Dosing Framework
The typical dosing approach for buspirone follows this structure:
- Initial dose: 5 mg twice daily 1
- Target therapeutic range: 15-30 mg per day in divided doses 2
- Maximum recommended dose: 20 mg three times daily (60 mg total daily dose) 1
Evidence for Higher Doses
While 60 mg/day represents the standard maximum, clinical research demonstrates safety at higher doses:
- Up to 90 mg/day has been studied in controlled trials for major depression and found to be safe and well tolerated 3
- Most patients in long-term studies were successfully managed on 15-30 mg/day, though the protocols allowed for higher dosing when clinically indicated 2
- Individual case reports document successful treatment with doses ranging from 35-60 mg daily for conditions like PTSD 4
Dosing Schedule Considerations
Buspirone can be administered as either twice-daily (BID) or three-times-daily (TID) regimens with equivalent safety profiles:
- 15 mg BID versus 10 mg TID showed similar adverse event profiles, with BID dosing potentially offering better compliance 5
- The standard maximum of 60 mg/day can be given as either 20 mg TID or 30 mg BID 1, 5
Important Clinical Caveats
Dose adjustments are critical in specific populations:
- Hepatic impairment: Plasma concentrations increase 15-fold; use lower doses and monitor closely 6
- Renal impairment: Concentrations double; dose reduction warranted 6
- Drug interactions: Doses must be reduced when co-administered with CYP3A4 inhibitors (verapamil, diltiazem, erythromycin, itraconazole), which can substantially increase buspirone levels 6
Onset and Titration
- Clinical efficacy typically emerges within 2-4 weeks, though onset can range from 5-29 days 1, 4
- Doses should be increased gradually using increments of the initial dose every 5-7 days until therapeutic benefit or significant side effects occur 1
- Long-term use up to one year has demonstrated no withdrawal syndrome or new adverse effects when discontinued 2