Read the Patient Information Leaflet if available from your pharmacist before you start taking lumacaftor/ivacaftor and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth as directed by your doctor, usually twice daily (12 hours apart). Eat a fat-containing meal or snack just before or just after taking this medication. Examples include eggs, avocados, nuts, butter, peanut butter, cheese pizza, or whole-milk dairy products (such as whole milk, cheese, yogurt).

If you are taking the granules form of this medication, gently shake the packet before use. Open the packet and carefully pour the contents into a small bowl with 1 teaspoonful (5 milliliters) of soft food or liquid (such as yogurt, applesauce, pudding, milk, or juice). The soft food or liquid should be at or below room temperature. After mixing, take all of the mixture within 1 hour. Be sure to eat a fat-containing food as directed.

The dosage is based on your age, medical condition, response to treatment, and other medications you may be taking. Children's dosage may also be based on weight. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day. If your dose is temporarily stopped for longer than 1 week, ask your doctor for specific directions to restart this medication. If you are taking certain other medications, you may be directed to restart at a lower dose for the first week.

Tell your doctor if your condition does not get better or if it gets worse.