Why is this medication prescribed?
Ivacaftor is used to treat certain types of cystic fibrosis (an inborn disease that causes problems with breathing, digestion, and reproduction) in adults and children 6 years of age and older. Ivacaftor should be used only in people with a certain genetic make-up. Your doctor may order a blood test to help decide if this medication is right for you. Ivacaftor is in a class of medications called cystic fibrosis transmembrane conductance regulator (CFTR) potentiators. It works by improving the function of a protein in the body to decrease the build-up of thick mucus in the lungs and improving other symptoms of cystic fibrosis.
How should this medicine be used?
Ivacaftor comes as a tablet to take by mouth. It is usually taken with fatty foods twice a day, 12 hours apart. Take ivacaftor at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ivacaftor exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Take ivacaftor with fatty foods such as eggs, butter, peanut butter, and cheese pizza. Talk to your doctor about other fatty foods to eat with ivacaftor.
Ivacaftor controls cystic fibrosis but does not cure it. Continue to take ivacaftor even if you feel well. Do not stop taking ivacaftor without talking to your doctor.
Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking ivacaftor,
- tell your doctor and pharmacist if you are allergic to ivacaftor, any other medications, or any of the ingredients in ivacaftor tablets. Ask your pharmacist for a list of the ingredients.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, you are taking or plan to take. Be sure to mention any of the following: alprazolam (Niravam, Xanax); certain antibiotics such as clarithromycin (Biaxin, in PrevPac), erythromycin (E.E.S., E-Mycin, Ery-Tab, Erythrocin), and telithromycin (Ketek); certain antifungals such as fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), posaconazole (Noxafil), and voriconazole (Vfend); cyclosporine (Gengraf, Neoral, Sandimmune); diazepam (Diastat, Valium); digoxin (Digitek, Lanoxicaps, Lanoxin); certain medications for seizures such as carbamazepine (Carbatrol, Epitol, Tegretol), phenobarbital (Luminal), and phenytoin (Dilantin, Phenytek); midazolam; rifabutin (Mycobutin); rifampin (Rifadin, in Rifamate, in Rifater, Rimactane); tacrolimus (Prograf); triazolam (Halcion); and warfarin (Coumadin, Jantoven). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with ivacaftor, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- tell your doctor what herbal products you are taking, especially St. John's wort.
- tell your doctor if you have or have ever had liver or kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking ivacaftor, call your doctor.
- you should know that ivacaftor may make you dizzy. Do not drive a car or operate machinery until you know how this medication affects you.
What special dietary instructions should I follow?
Do not eat grapefruit or Seville oranges or drink grapefruit juice while taking this medication.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Ivacaftor may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- joint pain
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- loss of appetite
- pain in the upper right part of the stomach
- dark urine
- extreme tiredness
- unusual bleeding or bruising
- yellowing of the skin or eyes
Ivacaftor may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].
What should I know about storage and disposal of this medication?
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). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests 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.