Drug Interaction Report

Telaprevir may significantly increase the blood levels of larotrectinib. This may increase the risk and/or severity of side effects such as dizziness, confusion, coordination problems, memory problems, liver problems, and tingling, numbness or burning in the hands and feet. 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. You should seek immediate medical attention 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.

Food significantly increases the absorption of telaprevir. Within 30 minutes before you take each dose of telaprevir, you should eat a meal or snack containing approximately 20 grams of fat. Taking it on an empty stomach may lead to inadequate blood levels and reduced effectiveness of the medication. Examples of some foods that could be taken with telaprevir include: bagel with cream cheese; half cup of nuts; 3 tablespoons of peanut butter; 1 cup of ice cream; 2 ounces of American or cheddar cheese; 2 ounces of potato chips; or half cup of trail mix. Talk to your healthcare provider if you have additional questions about how to take telaprevir.

Grapefruit juice can increase the blood levels of larotrectinib. This may increase the risk and/or severity of side effects such as dizziness, confusion, coordination problems, memory problems, liver problems, and tingling, numbness or burning in the hands and feet. You should avoid the consumption of grapefruit and grapefruit juice during treatment with larotrectinib. Talk to your doctor or pharmacist if you have questions on 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.