Lapatinib and Quinine interaction
Lapatinib and Quinine: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Moderate
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Lapatinib (TYKERB) label · effective 2026-01-27
Moderate
TYKERB may prolong the QT interval in some patients.
From the Quinine (QUININE SULFATE) label · effective 2025-10-31
Minor
Quinine inhibits P-gp and has the potential to affect the transport of drugs that are P-gp substrates.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.