Buspirone Starting Dose
Start buspirone at 15 mg daily (7.5 mg twice daily) with a plan to titrate upward by 5 mg per day every 2-3 days as needed, with the patient returning in one month for reassessment. 1
Recommended Initial Dosing
The FDA-approved starting dose is 15 mg daily, administered as 7.5 mg twice daily 1. This represents the standard initial dose across multiple guidelines and is supported by clinical trial data showing that divided doses of 20-30 mg per day were commonly employed and effective 1, 2.
Titration Strategy for One-Month Follow-Up
- Increase by 5 mg per day every 2-3 days as needed to achieve optimal therapeutic response 1
- Most patients are successfully managed on 15-30 mg daily in long-term studies 3
- Maximum daily dosage should not exceed 60 mg per day 1
- The pharmacokinetics are linear over the 10-40 mg dose range, making dose adjustments predictable 4
Critical Timing Considerations
Counsel the patient that buspirone requires 2-4 weeks to become effective 5. This "lag time" to onset of anxiolytic effect is well-documented 2, and patient motivation for compliance during this initial period is essential. With a one-month follow-up planned, the patient should just be reaching therapeutic benefit at the time of reassessment.
Important Administration Details
- Administer consistently with regard to food—either always with food or always without food 1
- Food increases bioavailability approximately 2-fold, affecting both peak concentration and overall exposure 1, 4
- The elimination half-life is approximately 2.5 hours, supporting twice-daily dosing 4
Special Population Considerations
For elderly or frail patients (as in the Alzheimer's guidelines), the initial dose of 5 mg twice daily may be more appropriate 5. However, for general adult populations without significant comorbidities, the standard 15 mg daily starting dose is preferred 1.
Common Pitfalls to Avoid
- Do not discontinue prematurely: The 2-4 week onset period means patients may perceive lack of efficacy before the drug has had adequate time to work 5, 2
- Avoid inconsistent food timing: Variable food intake can cause unpredictable plasma levels due to the 2-fold bioavailability difference 1, 4
- Screen for CYP3A4 inhibitors: Drugs like erythromycin, itraconazole, verapamil, and diltiazem substantially increase buspirone levels and require dose reduction 1, 4
- Allow 14 days when switching from MAOIs: This washout period is mandatory to avoid serotonin syndrome 1
Advantages Over Benzodiazepines
Buspirone lacks the sedation, cognitive impairment, abuse potential, and withdrawal syndrome associated with benzodiazepines 2, 3. Sedation occurs much less frequently than with benzodiazepines, and buspirone does not impair psychomotor or cognitive function 2. After abrupt discontinuation following more than six months of therapy, no withdrawal syndrome has been documented 3.