Drug Interaction Report

Ivacaftor may increase the blood levels of colchicine to dangerous levels, increasing the risk of serious side effects that can affect your muscles, blood cells, nervous system, and multiple organs including the liver and kidneys. Before taking colchicine let your doctor know if you are currently using ivacaftor or have used it within the last 14 days. Depending on your condition and the brand of colchicine you take, your doctor may interrupt treatment with colchicine, lower your dose of colchicine, or may decrease the frequency of colchicine doses. Let your doctor know if you experience abdominal pain, nausea, vomiting, diarrhea, fever, muscle pain, weakness, fatigue, and/or numbness or tingling in your hands and feet, as these may be early symptoms of colchicine toxicity. You may not be able to take these medications together if you have liver or kidney disease. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Drinking large amounts of grapefruit juice can increase your blood levels of colchicine to dangerous levels. You should avoid the consumption of grapefruit or grapefruit juice during treatment with colchicine. Let your doctor know if you experience abdominal pain, nausea, vomiting, diarrhea, fever, muscle pain, weakness, fatigue, and/or numbness or tingling in your hands and feet, as these may be early symptoms of colchicine toxicity.

Ivacaftor should be taken with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products to help with its absorption. Do not consume grapefruit juice or any food that contains grapefruit or Seville oranges during treatment with ivacaftor unless directed otherwise by your doctor. Grapefruit juice can significantly increase the blood levels of ivacaftor. This may increase the risk and/or severity of serious side effects such as liver damage. Call your doctor immediately if you have fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, abdominal pain, dark urine, pale stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.