Some foods don’t mix with drugs

Think of your stomach as one big test tube. Maybe you drop in a vitamin or herbal supplement each morning. Maybe a cholesterol-lowering statin or a blood-pressure drug. Perhaps an infection-fighting antibiotic or allergy-relieving antihistamine. And you wash it down with fruit juice or milk or coffee.

That may not always be a good thing because some foods and beverages — from chocolate and caffeine to dairy and alcohol — as well as dietary supplements (vitamins, herbals, etc.) and over-the-counter (OTC) drugs can interact with prescription drugs when they land in your gut.

Those interactions may affect the ability of the drug to work as it should. Or that mix may cause unwanted side effects.

With some tetracyclines, for example, you may need to avoid dairy products at the time you take the drug. If you take digoxin for your heart, you may need to steer clear of St. John’s wort and large amounts of black licorice (that contains glycyrrhizin).

Take ACE Inhibitors to lower your blood pressure? Go easy on high potassium foods such as bananas, oranges and green leafy vegetables. And depending on the statin you’re taking you may need to avoid grapefruit.

Such drug, food and supplement interactions become especially important as the number of drugs taken increases.

In the population 57 and older in the U.S., at least 80 percent use at least one prescription drug. Half of them use OTC drugs. And some use dietary supplements.

What is important in that report is that almost 30 percent use more than five drugs. And among those who take a prescription drug, half of them take either OTC or dietary supplements.

It is the dietary supplements we have to be very careful (about) and doctors need to be told about them.

Because your age, gender, medical history, etc. can affect how a drug interacts with other substances in your gut, there are no general rules. The key is for patients to be very open, to work with their pharmacist and physician and tell them about the use of supplements or vitamins.

That’s crucial because guidelines can change. The FDA regularly releases food-and-drug interaction consumer updates that are prompted by a variety of factors. So what should you use to help the medicine go down? Stick to a plain glass of water, say experts.