Drug Interaction Report

Ivacaftor may increase the blood levels of trabectedin in some patients. This can increase the risk and/or severity of side effects such as nausea, vomiting, constipation, diarrhea, liver problems, heart muscle problems (e.G., heart failure), and impaired bone marrow function resulting in low numbers of different types of blood cells. You may be more likely to develop anemia, bleeding problems, and infections because of low blood cell counts. In addition, your may have an increased risk of developing a rare but serious condition called rhabdomyolysis that involves the breakdown of skeletal muscle tissue. In some cases, rhabdomyolysis can cause kidney damage and even death. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Let your doctor know immediately if you have unexplained muscle pain, tenderness, or weakness during treatment with trabectedin, especially if these symptoms are accompanied by fever or dark colored urine. You should also seek immediate medical attention if you develop fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, 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.

Do not consume grapefruit or grapefruit juice during treatment with trabectedin, as it may increase blood levels of the medication. This can increase the risk and/or severity of side effects such as nausea, vomiting, constipation, diarrhea, liver problems, heart muscle problems (e.G., heart failure), and impaired bone marrow function resulting in low numbers of different types of blood cells. You may be more likely to develop anemia, bleeding problems, and infections because of low blood cell counts. In addition, your may have an increased risk of developing a rare but serious condition called rhabdomyolysis that involves the breakdown of skeletal muscle tissue. In some cases, rhabdomyolysis can cause kidney damage and even death. Talk to your doctor if you have any questions or concerns. Let your doctor know immediately if you have unexplained muscle pain, tenderness, or weakness during treatment with trabectedin, especially if these symptoms are accompanied by fever or dark colored urine. You should also seek immediate medical attention if you develop fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. Avoid excessive use of alcohol, as it may add to the effects of trabectedin on the liver. 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.

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.