A food-medicine interaction is when a food or drink changes how a medicine works. This can happen with both prescription and over-the-counter (OTC) medicines, including:

• Antacids.
• Vitamins.
• Iron pills.
• Herbs.
• Supplements.
• Prescribed medicines, such as some oral medicines for diabetes, antidepressants, and cholesterol medicines.

Some nutrients can affect the way you absorb certain medicines by binding with the medicine's ingredients. This reduces their absorption or speeds their elimination. For example:

• The acidity of fruit juice may reduce how well antibiotics, such as penicillin, work.
• Dairy foods and drinks may lower how well tetracycline fights infection.
• Some green leafy vegetables can stop the effects of warfarin. This is a blood thinner (anticoagulant).
• MAO inhibitors are not safe when mixed with foods or drinks that have tyramine. These include beer, red wine, chocolate, processed meat, avocados, and some cheeses.
• Grapefruit juice can interfere with some blood pressure medicines, organ transplant medicines, and some cholesterol-lowering medicines. It does this by increasing or decreasing how they break down in the body.
• Some medicines are only absorbed if they are taken with a full meal, a meal high in fat, or on an empty stomach.

Not all medicines are affected by food. But many can be affected by what you eat and when you eat it. In some cases, taking medicines at the same time you eat may change the way your stomach and intestines absorb medicine. Other medicines should be taken with food. Talk with your doctor or pharmacist. Ask for advice about how to take your medicine.

Always:

• Ask your pharmacist or doctor if there are foods, beverages, vitamins, or supplements you should not have with your medicines.
• Read the label on the container. If you don't understand something, ask your doctor or pharmacist.
• Read directions, warnings, and interaction precautions printed on all medicine labels. This includes over-the-counter (OTC) medicines. Even these can interact with foods, drinks, or supplements.
• Take medicine with a full glass of water unless told otherwise by your pharmacist or doctor.
• Do not stir medicine into your food or take capsules apart unless directed by your pharmacist or doctor. This may change the way the medicine works. Some medicines lose their delayed-onset effect when they are cut in half.
• Check with your pharmacist or doctor before taking vitamin pills at the same time you take medicine. This is because vitamins and minerals can interact with some medicines.
• Do not mix medicine into hot drinks. This is because the heat from the drink may reduce how well the medicine works.
• Do not take medicine with alcoholic drinks. Alcohol can change medicine absorption. And it may increase or decrease how well many medicines work.
• Tell your doctor about all of the medicines you are taking. This includes both prescription and OTC medicines.
• Get all your medicines from the same pharmacy. Tell your pharmacist about any OTC medicines, supplements, herbs, or vitamins that you take.
• Keep all medicines in their original containers. This is so they can be easily identified.