Drug interactions
Buspirone + St john's wort
Severity: Major
Buspirone and St john's wort: major interaction.
Last updated Sources: UK SmPC
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
St John's wort induces CYP3A4 and may reduce buspirone exposure, while both have serotonergic activity and may cause serotonin toxicity. The net effect is unpredictable.
What this interaction means in plain words
Buspirone and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
CYP3A4 induction by hyperforin lowers buspirone levels, and additive serotonergic effects are possible.
What to do
Avoid the combination and advise patients to stop St John's wort. Monitor for serotonin syndrome and for loss of anxiolytic effect.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Buspirone and St john's wort, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
Other interactions of Buspirone
- Buspirone + Isocarboxazid Contraindicated
- Buspirone + Linezolid Contraindicated
- Buspirone + Phenelzine Contraindicated
- Buspirone + Procarbazine Contraindicated
- Buspirone + Selegiline Contraindicated
- Buspirone + Selegiline transdermal Contraindicated
Frequently asked questions
Can I take Buspirone with St john's wort?
MediHelp rates the interaction as major. Buspirone and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. St John's wort induces CYP3A4 and may reduce buspirone exposure, while both have serotonergic activity and may cause serotonin toxicity. The net effect is unpredictable.
How serious is the interaction between Buspirone and St john's wort?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination and advise patients to stop St John's wort. Monitor for serotonin syndrome and for loss of anxiolytic effect.
What other medicines interact with Buspirone?
MediHelp also lists interactions of Buspirone with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Buspirone page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
