Drug interactions
Clarithromycin + Quetiapine
Severity: Major
Clarithromycin and Quetiapine: major interaction.
Last updated Sources: US FDA label
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
Clarithromycin substantially increases quetiapine exposure, leading to excess sedation, hypotension and QT prolongation. Quetiapine labeling recommends a dose reduction with strong CYP3A4 inhibitors.
What this interaction means in plain words
Clarithromycin and Quetiapine 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.
Clarithromycin belongs to Anti Bacterial; Quetiapine belongs to Central Nervous System.
Why it happens
Strong CYP3A4 inhibition reduces quetiapine clearance, with added QT effects.
What to do
Avoid if possible; otherwise reduce quetiapine to about one sixth of the usual dose per labeling and monitor sedation, blood pressure and ECG. Restore the dose after stopping clarithromycin.
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 Clarithromycin and Quetiapine, 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 Clarithromycin
- Astemizole + Clarithromycin Contraindicated
- Avanafil + Clarithromycin Contraindicated
- Cisapride + Clarithromycin Contraindicated
- Clarithromycin + Colchicine Contraindicated
- Clarithromycin + Conivaptan Contraindicated
- Clarithromycin + Dihydroergotamine Contraindicated
Other interactions of Quetiapine
- Adagrasib + Quetiapine Major
- Amiodarone + Quetiapine Major
- Amisulpride + Quetiapine Major
- Amoxapine + Quetiapine Major
- Anagrelide + Quetiapine Major
- Apalutamide + Quetiapine Major
Frequently asked questions
Can I take Clarithromycin with Quetiapine?
MediHelp rates the interaction as major. Clarithromycin and Quetiapine 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. Clarithromycin substantially increases quetiapine exposure, leading to excess sedation, hypotension and QT prolongation. Quetiapine labeling recommends a dose reduction with strong CYP3A4 inhibitors.
How serious is the interaction between Clarithromycin and Quetiapine?
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 if possible; otherwise reduce quetiapine to about one sixth of the usual dose per labeling and monitor sedation, blood pressure and ECG. Restore the dose after stopping clarithromycin.
What other medicines interact with Clarithromycin?
MediHelp also lists interactions of Clarithromycin with, for example, Astemizole, Avanafil, Cisapride. The full list is on the Clarithromycin 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.
