Buspirone Augmentation with Escitalopram: Recommended Dosing
When augmenting escitalopram (Lexapro) with buspirone (Buspar), the recommended initial dosing is 5 mg of buspirone twice daily, which can be gradually increased to a maximum of 20 mg three times daily based on clinical response and tolerability. 1
Buspirone Dosing Protocol
- Start with 5 mg of buspirone twice daily 1
- Gradually increase the dose every 3-7 days as tolerated 1
- Target dose range: 15-60 mg/day in divided doses 1, 2
- Maximum recommended dose: 20 mg three times daily (60 mg/day) 1
- Allow 2-4 weeks for buspirone to become fully effective 1
Escitalopram Considerations
- Standard escitalopram dosing should be maintained (10-20 mg daily) 1
- Monitor for potential serotonin-related side effects when combining with buspirone 1
- Escitalopram may be taken in the morning or evening depending on tolerability 1
Evidence for Augmentation Strategy
- Buspirone augmentation has shown efficacy in patients with depression who have had an inadequate response to SSRIs 3, 4
- In clinical studies, 59% of patients showed complete or partial remission when buspirone was added to SSRI treatment 3
- Patients with more severe depression (Montgomery-Asberg Depression Rating Scale scores >30) may benefit most from buspirone augmentation 4
- Buspirone augmentation may accelerate antidepressant response in patients who are refractory to treatment with SSRIs like escitalopram 4
Monitoring and Adjustments
- Evaluate clinical response after 2-4 weeks of treatment at a stable dose 1
- If inadequate response, increase buspirone dose gradually while monitoring for side effects 1
- A full therapeutic trial requires at least 4-8 weeks at an adequate dose 1
- If no significant improvement after 6-8 weeks of combined therapy at optimal doses, consider alternative strategies 1
Pharmacokinetic Considerations
- Buspirone has a short half-life (approximately 2.5 hours) requiring multiple daily dosing 2
- Food increases buspirone bioavailability by approximately 2-fold 2
- Buspirone undergoes extensive first-pass metabolism with only about 4% bioavailability 2
- Dose adjustments are necessary in patients with hepatic impairment 2
Potential Side Effects and Precautions
- Common side effects include dizziness, headache, nervousness, and nausea 2, 5
- Unlike benzodiazepines, buspirone has minimal risk of dependence or withdrawal symptoms 5
- Buspirone has minimal impact on platelet function, making it suitable for patients with bleeding concerns 5
- Avoid concomitant use with strong CYP3A4 inhibitors (e.g., erythromycin, itraconazole) which can significantly increase buspirone levels 2
This augmentation strategy provides an alternative approach for patients with depression who have had an inadequate response to escitalopram monotherapy, with a favorable side effect profile compared to other augmentation strategies.