Drug Interaction Report

Ketoconazole may significantly increase the blood levels and effects of futibatinib. High levels of futibatinib can increase the risk and/or severity of side effects including dry or inflamed eyes, inflamed cornea, increased tears, disorder of the retina, high phosphate levels in your blood, redness, swelling, peeling or tenderness, mainly on the hands or feet, nails separating from the bed or poor formation of the nail, urinary tract infection, constipation, diarrhea, dry mouth, abdominal pain, fatigue, muscle and joint pain, decreased levels of blood cells (white blood cells, red blood cells, and platelets), and changes in liver function blood tests. 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 to safely use both medications. 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.

Grapefruit juice can increase the blood levels of futibatinib. This may increase side effects including dry or inflamed eyes, inflamed cornea, increased tears, disorder of the retina, high phosphate levels in your blood, redness, swelling, peeling or tenderness, mainly on the hands or feet, nails separating from the bed or poor formation of the nail, urinary tract infection, constipation, diarrhea, dry mouth, abdominal pain, fatigue, muscle and joint pain, decreased levels of blood cells (white blood cells, red blood cells, and platelets), and changes in liver function blood tests. You should avoid the consumption of grapefruit and grapefruit juice during treatment with futibatinib. Be sure to take the medication at approximately the same time every day to maintain consistent blood levels and effects. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. 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.

You should avoid the use of alcohol while being treated with ketoconazole. Ketoconazole may cause liver damage and using it with alcohol or products containing alcohol may increase that risk. In addition, consumption of alcoholic beverages or products containing alcohol during treatment with ketoconazole may trigger a disulfiram-like reaction in some patients, with unpleasant symptoms such as flushing, palpitations, and nausea. Ketoconazole may be taken with or without food. You should avoid consumption of grapefruit, grapefruit juice, or any supplements that contain grapefruit extract during treatment with ketoconazole unless directed otherwise by your doctor. Grapefruit juice may increase the blood levels of ketoconazole. This may increase the risk and/or severity of side effects and liver problems. You should seek immediate medical attention if you develop signs and symptoms of liver damage during treatment with ketoconazole, such as joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, light colored stools, and yellowing of the skin or eyes. Talk to your doctor if you have any questions or concerns. 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.