Monoamine oxidase inhibitors are antidepressants used by patients who have not responded to other antidepressant therapies, according to the National Institutes of Health. Patients taking MAOIs face dietary restrictions that limit the consumption of foods containing high levels of tyramine. The interaction of tyramine with MAOIs can cause a dangerously high increase in blood pressure, which can lead to a stroke. Tyramine is found in foods that are fermented, aged, or spoiled.
Aged Cheese and Matured Cheese
Patients taking MAOIs should avoid aged cheese and matured cheese because they contain high levels of tyramine, according to the National Institutes of Health. The only cheeses that can be eaten are cottage cheese, cream cheese, ricotta, part-skim mozzarella and American processed cheese. These types of cheese are allowed as long as they have been refrigerated for no more than two or three weeks. Normally, monoamine oxidase enzyme in the digestive tract keeps tyramine levels within a safe range. Taking MAOIs prevents monoamine oxidase enzyme from working, resulting in elevated levels of tyramine. When tyramine levels increase, they can cause potentially serious reactions such as severe high blood pressure, headaches, heart problems, nausea, vomiting, visual disturbances, and confusion. For this reason, patients need to avoid eating aged cheese and matured cheese that contain significant amounts of tyramine.
Meats, Dairy Products and Fruits and Vegetables
Patients taking MAOIs should avoid smoked or pickled meats and cured meats such as sausages, salami, pastrami, mortadella and pepperoni, according to MayoClinic.com. Fresh packaged meat, fish, poultry and dairy products should be stored in the refrigerator and eaten within three to four days. Fermented vegetables and sauces should also be avoided by patients taking MAOIs. Examples of fermented vegetable products include tofu, sauerkraut, soy sauce, yeast extracts, teriyaki, soybean paste, miso soup, tamari, natto, shoyu, and tempeh. Examples of fruits containing tyramine that should be avoided by patients taking MAOIs include raspberries, bananas, avocado, spinach and banana peels. Foods containing monosodium glutamate are high in tyramine and should be avoided.
Patients taking MAOIs should limit the intake of beer, wine and liquor to no more than two servings a day, according to the National Institutes of Health. Tap beer or unpasteurized beer and red wine should be avoided, according to MayoClinic.com. Chocolate and caffeinated beverages should also be avoided.