Drug interactions
Lapatinib + Midazolam
Severity: Moderate
Lapatinib and Midazolam: 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
Lapatinib inhibits CYP3A4 and may raise midazolam concentrations. Sedation may be increased and prolonged.
What this interaction means in plain words
Lapatinib and Midazolam 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; Midazolam belongs to Central Nervous System.
Why it happens
Lapatinib inhibits CYP3A4, reducing midazolam metabolism.
What to do
Reduce midazolam dose and monitor sedation and respiration. Prefer a non-CYP3A4 benzodiazepine if oral dosing is needed.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Lapatinib and Midazolam, 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 Midazolam
- Atazanavir + Midazolam Contraindicated
- Cobicistat + Midazolam Contraindicated
- Darunavir + Midazolam Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Midazolam Contraindicated
- Fosamprenavir + Midazolam Contraindicated
- Indinavir + Midazolam Contraindicated
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 Lapatinib with Midazolam?
MediHelp rates the interaction as moderate. Lapatinib and Midazolam 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 inhibits CYP3A4 and may raise midazolam concentrations. Sedation may be increased and prolonged.
How serious is the interaction between Lapatinib and Midazolam?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reduce midazolam dose and monitor sedation and respiration. Prefer a non-CYP3A4 benzodiazepine if oral dosing is needed.
What other medicines interact with Midazolam?
MediHelp also lists interactions of Midazolam with, for example, Atazanavir, Cobicistat, Darunavir. The full list is on the Midazolam 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.
