Drug interactions
Chloroquine + Olanzapine
Severity: Moderate
Chloroquine and Olanzapine: moderate interaction.
Last updated
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
Chloroquine prolongs the QT interval and olanzapine has a smaller QT effect, so the combination may add to arrhythmia risk. The risk is greater with electrolyte disturbance or cardiac disease.
What this interaction means in plain words
Chloroquine and Olanzapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Chloroquine belongs to Anti Parasitic; Olanzapine belongs to Central Nervous System.
Why it happens
Additive QT prolongation.
What to do
Check ECG and electrolytes at baseline in at-risk patients and monitor during co-therapy. Correct hypokalemia and hypomagnesemia.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Chloroquine and Olanzapine, 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.
Other interactions of Chloroquine
- Chloroquine + Cisapride Contraindicated
- Chloroquine + Dofetilide Contraindicated
- Chloroquine + Dronedarone Contraindicated
- Chloroquine + Droperidol Contraindicated
- Chloroquine + Panobinostat Contraindicated
- Chloroquine + Pimozide Contraindicated
Other interactions of Olanzapine
Frequently asked questions
Can I take Chloroquine with Olanzapine?
MediHelp rates the interaction as moderate. Chloroquine and Olanzapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Chloroquine prolongs the QT interval and olanzapine has a smaller QT effect, so the combination may add to arrhythmia risk. The risk is greater with electrolyte disturbance or cardiac disease.
How serious is the interaction between Chloroquine and Olanzapine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check ECG and electrolytes at baseline in at-risk patients and monitor during co-therapy. Correct hypokalemia and hypomagnesemia.
What other medicines interact with Chloroquine?
MediHelp also lists interactions of Chloroquine with, for example, Cisapride, Dofetilide, Dronedarone. The full list is on the Chloroquine 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.
