Read the Patient Information Leaflet if available from your pharmacist before you start taking 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 (every 12 hours). Take this medication with fat-containing foods (such as eggs, butter, peanut butter, cheese). The dosage is based on your medical condition, response to treatment, and other medications you may be taking. 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 time(s) each day.
Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Also avoid eating Seville oranges (often found in marmalade). Grapefruit and Seville oranges can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details.
Tell your doctor if your condition does not improve or if it worsens.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any side effects, including: vision changes.
Ivacaftor may rarely cause serious liver disease. Get medical help right away if you have any symptoms of liver damage, including: dark urine, persistent nausea/vomiting/loss of appetite, stomach/abdominal pain, yellowing eyes/skin.
Ivacaftor can commonly cause a rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe reaction. Therefore, tell your doctor right away if you develop any rash.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking ivacaftor, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
See also How To Use section.
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.
This medication can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include some benzodiazepines (such as alprazolam, triazolam), cyclosporine, digoxin, tacrolimus, among others.
Other medications can affect the removal of ivacaftor from your body, which may affect how ivacaftor works. Examples include azole antifungals (such as fluconazole, itraconazole, ketoconazole), macrolide antibiotics (such as clarithromycin, erythromycin), rifamycins (such as rifabutin), drugs for seizures (such as carbamazepine, phenytoin), St. John's wort, telithromycin, among others.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Do not share this medication with others.
Laboratory and/or medical tests (such as CFTR gene testing, liver/lung function, eye exams) will be performed before starting and while you are taking this medication to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised January 2015. Copyright(c) 2015 First Databank, Inc.
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