Drug Interaction Report

Crizotinib may increase the blood levels of dalfampridine. This may increase the risk and/or severity of side effects such as nausea, insomnia, dizziness, weakness, headache, confusion, and seizures. Contact your doctor if your condition changes or you experience increased side effects during treatment with these medications. 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.

Do not consume grapefruit or grapefruit juice during treatment with crizotinib unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of crizotinib to dangerous levels and cause an irregular heart rhythm that may be serious. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or fast or pounding heartbeats during treatment with crizotinib. You may take crizotinib with or without food, but take it the same time each day. 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.