ANNOUNCER: All medicines have side effects, and patients are generally advised about them. But what many people don't realize is that medicines can react with other things we take into our bodies, as well as with other drugs.
JOHN HORN, PharmD: There are some situations when a person takes multiple medications where those medications might interact with each other in a non-desirable way.
Some drugs, when combined, can produce unexpected side effects. Other combinations can lead to decreased effectiveness for one drug or another. Other medicines have similar side effects, like drowsiness, and combining them may turn a tolerable side effect into a significant one.
ANNOUNCER: A common misunderstanding is that over-the-counter medicines are of no particular concern.
JOHN HORN, PharmD: Interactions can occur with prescription as well as non-prescription medications. There have been interactions that occur with over-the-counter cough and cold preparations, for example, some of the diet products, the ones containing ephedra have been involved in interactions. So over-the-counter products do have effectiveness. They do produce a pharmacologic response, and that response can be altered by another drug.
ANNOUNCER: Another misconception involves products commonly bought at the vitamin and herbal supplement shops.
JOHN HORN, PharmD: St. John's wort's kind of interesting in that it actually reduces the effectiveness of many other drugs. And I'll give you a very simple example of that. Oral contraceptives are metabolized in the body, and St. John's wort actually increases that rate of metabolism. So if you're taking an oral contraceptive and then you take St. John's wort, the oral contraceptive may, in fact, fail.
ANNOUNCER: These days, people may have several doctors. They may shop at several drug stores or order drugs by mail. But there's plenty a person can do to help keep all of their health professionals well informed.
JOHN HORN, PharmD: The most effective way to prevent harm from drug interactions is to be sure that everybody who you deal with, physicians, your prescribers, any health care provider, including dentists and your pharmacists, are aware of all the drugs you're taking. So a really simple way to do that is just simply keep a written list of what medicines you're taking. And that list should not just include prescription medicines, but also any vitamins, herbal supplements, other drugs or products that you might be buying from a health food store, all of those agents could conceivably interact with one or another.
ANNOUNCER: Health professionals say people should read labels, and take advantage of information often provided at the drug store.
JOHN HORN, PharmD: Patient package inserts are little sheets of paper that often put into the bag with the prescription product, and those are really intended to provide the patient with some basic information about the drug they're taking.
ANNOUNCER: And don't be surprised by the range of possible interactions. Some drugs, especially antibiotics, can lose effectiveness if taken with a certain antacids, or dairy products. Patients on some drugs may turn beet red if they're exposed to bright sunlight.
JOHN HORN, PharmD: Another example of a product that can produce interactions that we don't think about very often is grapefruit juice. This is actually a food, but there are some compounds in grapefruit juice which can interfere with the body's ability to eliminate certain medications, and that could lead to an increase in the amount of those medications in your body, and perhaps lead to an adverse effect.
ANNOUNCER: And finally, doctors and pharmacists say there's one more way to keep from harm's way when it comes to medications:
JOHN HORN, PharmD: Don't be afraid to ask questions. I think that's really important, that patients understand why they're taking medications and what the more common side effects might be from their medication.
ANNOUNCER: At the pharmacy, on drug store shelves, and at the health food store, consumers face many choices when it comes to products they feel may help keep them well. But keeping track of what you put in your body, and being mindful of how these chemicals may interact, is a key to drug safety.