Drug interactions
Olanzapine + Vandetanib
Severity: Major
Olanzapine and Vandetanib: major 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
Vandetanib causes marked, dose-related QT prolongation with a boxed warning for torsades de pointes and sudden death. Adding olanzapine, which has a smaller QT effect, adds further risk.
What this interaction means in plain words
Olanzapine and Vandetanib 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.
Olanzapine belongs to Central Nervous System; Vandetanib belongs to Oncology.
Why it happens
Additive prolongation of cardiac repolarization through hERG potassium channel blockade.
What to do
Avoid the combination where possible and choose an antipsychotic or antiemetic with less QT liability. If unavoidable, monitor ECG and keep potassium, magnesium and calcium normal.
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 Olanzapine and Vandetanib, 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 14 days on the web. No card needed.
Other interactions of Olanzapine
Other interactions of Vandetanib
- Amiodarone + Vandetanib Contraindicated
- Amisulpride + Vandetanib Contraindicated
- Amitriptyline + Vandetanib Contraindicated
- Anagrelide + Vandetanib Contraindicated
- Asenapine + Vandetanib Contraindicated
- Chloroquine + Vandetanib Contraindicated
Frequently asked questions
Can I take Olanzapine with Vandetanib?
MediHelp rates the interaction as major. Olanzapine and Vandetanib 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. Vandetanib causes marked, dose-related QT prolongation with a boxed warning for torsades de pointes and sudden death. Adding olanzapine, which has a smaller QT effect, adds further risk.
How serious is the interaction between Olanzapine and Vandetanib?
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 where possible and choose an antipsychotic or antiemetic with less QT liability. If unavoidable, monitor ECG and keep potassium, magnesium and calcium normal.
What other medicines interact with Olanzapine?
MediHelp also lists interactions of Olanzapine with, for example, Amisulpride, Amoxapine, Apomorphine. The full list is on the Olanzapine 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.
