Drug interactions
Danazol + Lapatinib
Severity: Moderate
Danazol and Lapatinib: 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
Danazol is a weak to moderate CYP3A4 inhibitor and may raise lapatinib concentrations. This could increase lapatinib toxicity such as diarrhea, hepatotoxicity and QT prolongation.
What this interaction means in plain words
Danazol and Lapatinib 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.
Why it happens
Danazol inhibits CYP3A4, reducing lapatinib metabolism.
What to do
Monitor liver function, QTc and diarrhea, and consider an alternative to danazol. Reduce the lapatinib dose if toxicity develops.
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
Frequently asked questions
Can I take Danazol with Lapatinib?
MediHelp rates the interaction as moderate. Danazol and Lapatinib 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. Danazol is a weak to moderate CYP3A4 inhibitor and may raise lapatinib concentrations. This could increase lapatinib toxicity such as diarrhea, hepatotoxicity and QT prolongation.
How serious is the interaction between Danazol and Lapatinib?
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 liver function, QTc and diarrhea, and consider an alternative to danazol. Reduce the lapatinib dose if toxicity develops.
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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