Ivacaftor is used to treat cystic fibrosis in adults and children who are at least 1 month old and weigh at least 6 pounds (3 kilograms).

Ivacaftor tablet can be used in children aged 6 years and older. Ivacaftor granules can be used in children aged 1 month to under 6 years old.

Your doctor will make sure you have the specific gene mutation related to cystic fibrosis to be treated with ivacaftor.

Ivacaftor may also be used for purposes not listed in this medication guide.

Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Take ivacaftor with food that contains fat, such as eggs, milk products such as whole milk, cheese, yogurt, breast milk or infant formula. Follow your doctor's instructions carefully.

Swallow the tablet whole and do not crush, chew, or break it.

Mix the ivacaftor granules with 1 teaspoon of soft food such as pureed fruits or vegetables, yogurt, applesauce, water, breast milk, infant formula, milk, or juice. Mix only 1 dose at a time and use within 1 hour after mixing. Feed the child a high-fat food after or before giving the granule mixture.

Take this medicine at evenly spaced intervals every 12 hours.

Doses are based on weight in children. Your child's dose may change if the child gains or loses weight.

You will need frequent blood tests to check your liver function.

Your child may need frequent vision exams.

Store at room temperature away from moisture and heat. Keep the medicine in the original packaging.

Usual Adult Dose for Cystic Fibrosis:

150 mg orally every 12 hours with fat containing food

Comments:
-Examples of fat-containing food include: eggs, butter, peanut butter, cheese pizza, and whole milk dairy products.
-If the patient's genotype is unknown, an approved CF mutation test should be used to detect the presence of a CFTR mutation followed by verification with bi-directional sequencing when recommended by the mutation test instructions for use.

Uses:
-For the treatment of cystic fibrosis in patients having one mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that is responsive to ivacaftor potentiation based on clinical and/or in vitro assay data.

Usual Pediatric Dose for Cystic Fibrosis:

Oral Granules:
Age: 4 months to less than 6 months:
Weight: 5 kg or greater: 25 mg orally every 12 hours
-Use is not recommended in the presence of hepatic impairment or in those taking concomitant moderate or strong CYP450 3A inhibitors

Age: 6 months or older:
Weight: 5 to less than 7 kg: 25 mg orally every 12 hours
Weight: 7 to less than 14 kg: 50 mg orally every 12 hours
Weight: 14 kg or greater: 75 mg orally every 12 hours

Oral Tablet:
Age: 6 years and older: 150 mg orally every 12 hours

Comments:
-Doses should be taken just before or after fat-containing food; examples of fat-containing food include: eggs, butter, peanut butter, cheese pizza, and whole milk dairy products.
-Dose adjustments are recommended for patients 6 months or older with hepatic impairment and/or taking concomitant moderate or strong CYP450 3A inhibitors.
-If the patient's genotype is unknown, an FDA-cleared CF mutation test should be used to detect the presence of a CFTR mutation followed by verification with bi-directional sequencing when recommended by the mutation test instructions for use.

Uses:
-For the treatment of cystic fibrosis in patients 4 months or older having one mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that is responsive to ivacaftor potentiation based on clinical and/or in vitro assay data.

You should not be treated with ivacaftor if you are allergic to it, or if you have or have ever had:

• liver or kidney disease.

It is not known if ivacaftor will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using ivacaftor.

Take the medicine as soon as you can, with a fatty meal, but skip the missed dose if you are more than 6 hours late for the dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Do not eat grapefruit or drink grapefruit juice while taking this medication.

Avoid driving or hazardous activity until you know how ivacaftor will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

Grapefruit may interact with ivacaftor and cause side effects. Avoid consuming grapefruit products.

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Ivacaftor may cause serious side effects. Call your doctor at once if you have:

• blurred vision, eye pain or redness, seeing halos around lights;

• low blood sugar--headache, hunger, weakness, sweating, confusion, irritability, dizziness, fast heart rate, or feeling jittery; or

• liver problems--loss of appetite, nausea, vomiting, stomach pain (upper right side), tiredness, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common side effects of ivacaftor may include:

• muscle or joint pain;

• dizziness;

• rash, acne;

• headache;

• mouth pain;

• stomach pain, nausea, diarrhea; or

• cold symptoms such as stuffy nose, sneezing, runny nose, sore throat.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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:

• St. John's wort;

• seizure medicine such as carbamazepine, phenobarbital, or phenytoin;

• an antibiotic--clarithromycin, erythromycin, telithromycin, rifabutin, rifampin; or

• antifungal medicine--fluconazole, itraconazole, ketoconazole, posaconazole, voriconazole.

This list is not complete. Other drugs may affect ivacaftor, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Keep all appointments with your doctor and the laboratory. Your doctor will order an eye exam and certain lab tests before and during your treatment to check your body's response to ivacaftor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.