Drug interactions
Lapatinib + Ribociclib
Severity: Major
Lapatinib and Ribociclib: 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
Both drugs prolong the QT interval, so combined use raises the risk of torsades de pointes. Ribociclib is also a CYP3A4 inhibitor and may increase lapatinib exposure, which adds to the risk.
What this interaction means in plain words
Lapatinib and Ribociclib 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.
Lapatinib belongs to Oncology; Ribociclib belongs to Oncology.
Why it happens
Additive QT prolongation, plus ribociclib inhibition of CYP3A4-mediated lapatinib metabolism.
What to do
Avoid the combination where possible. If it is unavoidable, check baseline and follow-up ECGs and electrolytes, and correct potassium and magnesium.
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?
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Other interactions of Lapatinib
- Dofetilide + Lapatinib Contraindicated
- Ibutilide + Lapatinib Contraindicated
- Lapatinib + Pimozide Contraindicated
- Lapatinib + Saquinavir Contraindicated
- Lapatinib + Thioridazine Contraindicated
- Adagrasib + Lapatinib Major
Other interactions of Ribociclib
- Amiodarone + Ribociclib Contraindicated
- Cisapride + Ribociclib Contraindicated
- Dofetilide + Ribociclib Contraindicated
- Dronedarone + Ribociclib Contraindicated
- Flibanserin + Ribociclib Contraindicated
- Ibutilide + Ribociclib Contraindicated
Frequently asked questions
Can I take Lapatinib with Ribociclib?
MediHelp rates the interaction as major. Lapatinib and Ribociclib 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. Both drugs prolong the QT interval, so combined use raises the risk of torsades de pointes. Ribociclib is also a CYP3A4 inhibitor and may increase lapatinib exposure, which adds to the risk.
How serious is the interaction between Lapatinib and Ribociclib?
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. If it is unavoidable, check baseline and follow-up ECGs and electrolytes, and correct potassium and magnesium.
What other medicines interact with Lapatinib?
MediHelp also lists interactions of Lapatinib with, for example, Dofetilide, Ibutilide, Pimozide. The full list is on the Lapatinib page.
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