Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Other medications can affect the removal of lumacaftor/ivacaftor from your body, which may affect how this medication works. Examples include mifepristone, rifamycins (such as rifampin, rifabutin), drugs for seizures (such as carbamazepine, phenytoin), St. John's wort, among others.

This medication can speed up the removal of other medications from your body, which may affect how they work. Examples of affected drugs include certain azole antifungals (such as isavuconazonium, voriconazole), macrolide antibiotics (such as erythromycin, clarithromycin), certain drugs that weaken the immune system (such as cyclosporine, everolimus, tacrolimus), nirmatrelvir, pacritinib, certain sedatives (such as midazolam, triazolam), warfarin, among others.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use reliable backup birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.