Deadly Drug Duos

By Christine Gorman

Doctors call it the brown-bag test. The idea is to have you dump the contents of your home medicine cabinet plus your favorite vitamins and over-the-counter remedies into a bag and bring it to their office so they can see just exactly which pills you're popping. The findings can be horrifying. You may discover that those little white tablets and the big blue gel caps you're swallowing are actually dangerous when taken together. The more prescription medicines you take, the greater the risk.

Got Hismanal (an allergy drug) and Nizoral (an anti-fungal medication) in that bag? Together they can trigger fatal cardiac spasms. Taking a little Viagra to boost your love life? Make sure you're not also on nitroglycerin for angina. In the past two months, that combination has killed four men, including one who, the Food and Drug Administration revealed last week, complained of chest pains after having sex and was given nitroglycerin in the ambulance. Now the FDA is trying to figure out if other drugs, like the prostate medication Hytrin, don't mix with Viagra.

Nonprescription drugs can cause problems too. Antacids, for example, can neutralize certain antibiotics called fluoroquinolones. High doses of vitamin E (over 400 IU) can trigger serious internal bleeding when taken with a blood-thinning agent like Coumadin. Even eating can be tricky. Grapefruit juice intensifies the effects of some high-blood-pressure medications (calcium channel blockers) while aged cheeses, wine and chocolate can turn antidepressants (MAO inhibitors) into poisons. And those are just some of the thousands of cross-reactions that pharmacists know about. New contraindications are added to the list all the time.

Just last week Roche Laboratories pulled its high-blood-pressure pill Posicor from the market because of potentially fatal interactions with 26 other medications, including such common cholesterol drugs as Mevacor and Zocor. If you are taking Posicor, however, don't just stop it on your own. Ask your doctor for a substitute prescription to keep your blood pressure safely under control.

You can never eliminate all the risks inherent in taking drugs, of course, even if you're taking just a single medication. A study in April's Journal of the American Medical Association estimated that at least 76,000 people die in the U.S. each year from bad reactions to prescription medications that were properly administered. But there are some simple guidelines to follow that will decrease your chances of becoming a medical statistic.

First, make sure all your doctors and pharmacists know all the drugs, including over-the-counter remedies, that you're taking. Most doctors routinely use just 20 of the more than 12,000 prescription products currently available. So don't be alarmed if they have to look a few things up. Pick up a copy of Deadly Drug Interactions by Joe and Teresa Graedon (St. Martin's Griffin). Keep a list of your medications and allergies in your wallet for emergencies. Fill all your prescriptions at the same pharmacy, preferably one that has a computerized system for flagging potential problems. And make sure you take only medications that are absolutely necessary. A change in diet or exercise can, in many cases, work just as well as yet another pill.

Get the FDA's latest Medwatch reports on drug reactions at fda.gov See time.com for a complete list of other web resources.