Drug Interactions between cabozantinib and erlotinib

Erlotinib should be taken on an empty stomach at least 1 hour before or 2 hours after a meal and at the same time each day unless otherwise directed by your doctor. You should also avoid grapefruit and grapefruit juice while taking erlotinib. Food and grapefruit juice can increase the absorption of erlotinib from the gastrointestinal tract, which may lead to higher blood levels of the medication and possibly increased side effects. If you are a smoker, you should try to quit as soon as you can. Cigarette smoking can reduce the blood levels of erlotinib, which may make the medication less effective in treating your cancer. It is best to avoid smoking during erlotinib therapy. Talk to a healthcare professional if you have any questions or concerns. If you start smoking or undergo smoking cessation, your doctor may need to adjust your dose of erlotinib. 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.

Cabozantinib should be taken on an empty stomach, one hour before or two hours after a meal. Do not consume grapefruit, grapefruit juice, or any supplements that contain grapefruit extract during treatment with cabozantinib unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of cabozantinib. You may be more likely to experience side effects such as nausea; vomiting; diarrhea; loss of appetite; weight loss; mouth sores; abdominal pain; skin rash (primarily on the palms of the hands and soles of the feet); delayed wound healing; high blood pressure; and impaired bone marrow function resulting in low numbers of different types of blood cells, which can increase the risk of bleeding problems and infections. 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.