Do not take this medicine with any of the following medications:

-certain medicines for seizures like carbamazepine, phenobarbital, phenytoin
-grapefruit juice
-rifampin
-rifabutin
-St. John''s Wort

This medicine may also interact with the following medications:

-certain antibiotics like clarithromycin, erythromycin, and telithromycin
-certain medicines for fungal infections like fluconazole, itraconazole, ketoconazole, posaconazole, and voriconazole
-cyclosporine
-digoxin
-everolimus
-sirolimus
-tacrolimus

They need to know if you have any of these conditions:

-kidney disease
-liver disease
-an unusual reaction to tezacaftor, ivacaftor, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.

Your vision and blood may be tested before and during use of this medicine.

Tell your doctor or health care professional right away if you have any change in your eyesight.

You may get dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. To avoid dizzy or fainting spells, do not stand or sit up quickly, especially if you are an older person. Alcohol can make you more drowsy and dizzy. Avoid alcoholic drinks.

Keep out of the reach of children.

Store at room temperature between 20 to 25 degrees C (68 to 77 degrees F). Throw away any unused medicine after the expiration date.