Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.
Tell your doctor about all your other medicines, especially ketoconazole. You should not take ketoconazole while you are being treated with abemaciclib.
Ketoconazole is a strong CYP3A4 inhibitor and coadministration of abemaciclib with strong CYP3A4 inhibitors should be avoided because they can increase abemaciclib concentrations.
Other medications that are strong CYP3A4 inhibitors include clarithromycin, itraconazole, lopinavir/ritonavir, posaconazole, and voriconazole. Grapefruit or grapefruit juice should also be avoided.
The dose of abemaciclib should be reduced if co-administered with moderate CYP3A4 inhibitors, such as
verapamil or diltiazem.
This list is not complete, see the Verzenio (abemaciclib) Prescribing Information for a full list. Other drugs may affect abemaciclib, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
