Drug Interactions between erlotinib and st. john's wort

While you are taking St. John's wort, you must not eat or drink certain foods and beverages that are high in tyramine. Eating these foods while you are taking St. John's wort can raise your blood pressure to dangerous levels. This may cause life threatening symptoms such as sudden and severe headache, confusion, blurred vision, problems with speech or balance, nausea, vomiting, chest pain, seizure (convulsions), and sudden numbness or weakness (especially on one side of the body). Call your doctor at once if you have any of these symptoms. Foods that are high in tyramine include: air dried meats, aged or fermented meats, sausage or salami, pickled herring, and any spoiled or improperly stored beef, poultry, fish, or liver, red wine, beer from a tap, beer that has not been pasteurize, aged cheeses, including blue, brick, brie, cheddar, parmesan, romano, and swiss, sauerkraut, over the counter supplements or cough and cold medicines that contain tyramine, soy beans, soy sauce, tofu, miso soup, bean curd, fava beans, or yeast extracts (such as Marmite). Caffeine intake should be limited as well. You should avoid or limit the use of alcohol while being treated with St. John's wort. Alcohol can increase the nervous system side effects of St. John's wort such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. Talk to your doctor or pharmacist if you have any questions or concerns.

Switch to professional interaction data

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.

Switch to professional interaction data