Precautions When Taking Buspar (Buspirone) with Citalopram
The combination of buspirone and citalopram can be used together, but requires careful monitoring for serotonin syndrome, particularly during the first 24-48 hours after initiation or dose changes, with slow dose titration starting at low doses. 1
Primary Safety Concern: Serotonin Syndrome
Monitor closely for serotonin syndrome when combining these two serotonergic medications. This potentially fatal condition can develop within 24-48 hours of combining medications and presents with: 1
- Mental status changes: confusion, agitation, anxiety
- Neuromuscular hyperactivity: tremors, clonus, hyperreflexia, muscle rigidity
- Autonomic hyperactivity: hypertension, tachycardia, arrhythmias, tachypnea, diaphoresis, shivering, vomiting, diarrhea
Advanced symptoms include fever, seizures, arrhythmias, and unconsciousness, which can lead to fatalities. 1 Case reports document serotonin syndrome occurring with buspirone combined with SSRIs like fluoxetine, confirming this is a real clinical risk. 2
Cardiac Monitoring Requirements
Check baseline ECG and monitor QT interval because citalopram can cause QT prolongation associated with Torsade de Pointes, ventricular tachycardia, and sudden death, particularly at daily doses exceeding 40 mg/day. 1 Citalopram should be avoided in patients with long QT syndrome. 1
Safe Initiation Protocol
Start buspirone at a low dose (5 mg twice daily) and increase slowly when adding to existing citalopram therapy. 1 The FDA label recommends initial dosing of 15 mg daily (7.5 mg twice daily), with increases of 5 mg per day at 2-3 day intervals as needed, up to a maximum of 60 mg daily. 3
Monitor intensively during the first 24-48 hours after any dose change for symptoms of serotonin syndrome. 1
MAOI Considerations
Ensure at least 14 days have elapsed since discontinuation of any MAOI before starting buspirone, and allow 14 days after stopping buspirone before starting an MAOI. 3 This includes reversible MAOIs like linezolid, which has been documented to cause serotonin syndrome when combined with buspirone. 4
Clinical Efficacy Context
Despite these precautions, this combination has demonstrated clinical utility. In the STAR*D trial, augmenting citalopram with buspirone achieved remission rates of 30.1% (HRSD-17) and 32.9% (QIDS-SR-16), though discontinuation due to intolerance was 20.6%. 1, 5 Buspirone augmentation of SSRIs has shown 59% complete or partial remission rates in treatment-resistant depression. 6
Common Pitfalls to Avoid
- Do not assume safety based on individual drug profiles alone - while buspirone has variable effects on 5-HT1A receptors that may reduce risk when given as monotherapy, adverse reactions can occur when combined with other serotonergic drugs. 2
- Do not miss early serotonin syndrome symptoms - therapeutic hypothermia or sedation can mask typical presentations, delaying diagnosis. 4
- Do not exceed citalopram 40 mg daily due to cardiac risk, with further dose reduction to 20 mg daily in patients over 60 years. 1
Patient Counseling
Instruct patients to immediately report symptoms of confusion, agitation, tremors, muscle rigidity, fever, rapid heartbeat, or profuse sweating. 1 Advise taking buspirone consistently either always with food or always without food, as bioavailability increases when taken with food. 3