Drug interactions
Lapatinib + Lenvatinib
Severity: Moderate
Lapatinib and Lenvatinib: 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
Both drugs can prolong the QT interval, so combined use raises the risk of ventricular arrhythmias.
What this interaction means in plain words
Lapatinib and Lenvatinib 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.
Lapatinib belongs to Oncology; Lenvatinib belongs to Oncology.
Why it happens
Additive pharmacodynamic QT interval prolongation.
What to do
Monitor ECG and keep potassium, magnesium and calcium within normal range; interrupt therapy if QTc becomes markedly prolonged.
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?
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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 Lenvatinib
- Amiodarone + Lenvatinib Major
- Amisulpride + Lenvatinib Major
- Asenapine + Lenvatinib Major
- Chlorpromazine + Lenvatinib Major
- Donepezil + Lenvatinib Major
- Haloperidol + Lenvatinib Major
Frequently asked questions
Can I take Lapatinib with Lenvatinib?
MediHelp rates the interaction as moderate. Lapatinib and Lenvatinib 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. Both drugs can prolong the QT interval, so combined use raises the risk of ventricular arrhythmias.
How serious is the interaction between Lapatinib and Lenvatinib?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor ECG and keep potassium, magnesium and calcium within normal range; interrupt therapy if QTc becomes markedly prolonged.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
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