Drug interactions
Ibutilide + Lapatinib
Severity: Contraindicated
Ibutilide and Lapatinib: contraindicated 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
Ibutilide strongly prolongs the QT interval and commonly causes torsades de pointes. Adding lapatinib, which also prolongs QT, further raises this risk.
What this interaction means in plain words
Ibutilide and Lapatinib are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Ibutilide belongs to Cardiovascular; Lapatinib belongs to Oncology.
Why it happens
Additive pharmacodynamic QT prolongation.
What to do
Avoid the combination. Choose another rhythm-control strategy, such as electrical cardioversion, in patients taking lapatinib.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Ibutilide and Lapatinib, 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 Lapatinib
- Dofetilide + Lapatinib Contraindicated
- Lapatinib + Pimozide Contraindicated
- Lapatinib + Saquinavir Contraindicated
- Lapatinib + Thioridazine Contraindicated
- Adagrasib + Lapatinib Major
- Amiodarone + Lapatinib Major
Other interactions of Ibutilide
- Amiodarone + Ibutilide Contraindicated
- Amisulpride + Ibutilide Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Clarithromycin + Ibutilide Contraindicated
- Desipramine + Ibutilide Contraindicated
- Dolasetron + Ibutilide Contraindicated
Frequently asked questions
Can I take Ibutilide with Lapatinib?
MediHelp rates the interaction as contraindicated. Ibutilide and Lapatinib are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Ibutilide strongly prolongs the QT interval and commonly causes torsades de pointes. Adding lapatinib, which also prolongs QT, further raises this risk.
How serious is the interaction between Ibutilide and Lapatinib?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination. Choose another rhythm-control strategy, such as electrical cardioversion, in patients taking lapatinib.
What other medicines interact with Lapatinib?
MediHelp also lists interactions of Lapatinib with, for example, Dofetilide, Pimozide, Saquinavir. The full list is on the Lapatinib 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.
