Drug Interaction Report

Larotrectinib may significantly reduce the blood levels of rifAMPin, which may make the medication less effective in treating your condition. 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.

Food can decrease the levels of rifAMPin in your body. Taking rifAMPin on an empty stomach (at least 30 minutes before or 2 hours after a meal) will make it easier for your body to absorb the medication. Avoid drinking alcohol while taking rifAMPin because alcohol use may increase the risk of damage to your liver. It is important to seek immediate medical care if you experience any severe side effects or symptoms of liver damage such as 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. 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 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.