One in 25 older Americans are taking drugs in combinations that could be risky, according to a new report published in the Journal of the American Medical Association. Half of the potentially dangerous mixes involve over-the-counter remedies or supplements.

The findings, drawn from interviews with 3005 Americans 57 to 85 years old conducted by the National Social Life, Health and Aging Project, offer both warning and reassurance. “We were reassured that we did not find combinations of the most commonly used drugs that were absolutely forbidden, one indication that drug safety systems used by physicians, nurses and pharmacists are working,” said Stacy Tessler Lindau, MD, assistant professor of medicine at the University of Chicago Medical Center and lead author of the study.

Still, the investigation did turn up potentially hazardous combinations, many involving over-the-counter medications and supplements taken along with prescription drugs.

Nearly half of the interactions could result in bleeding problems, the scientists said. Some respondents were taking warfarin along with aspirin, for example. Both drugs interfere with clotting and, in combination, can cause gastric and other bleeding problems. Another dangerous combination linked to bleeding problems: aspirin taken along with gingko, an herbal supplement.

Patients also reported taking cholesterol-lowering statins along with the mineral supplement naicin. In combination, these medications can increase the danger of muscle weakness and breakdown of muscle tissue.

Although the percentage of people taking medication hasn’t changed in recent years, the number of different pills they take has jumped. Ninety-one percent reported taking at least one medication on a daily basis. Almost one in three took five or more. With each additional medication, the risk of potentially dangerous interactions climbs.

Sixty-eight percent of those who took prescription drugs were also taking an OTC medication or supplement. Men were more likely to take OTCs and women more likely to take supplements. Both categories are of special concern, experts say, since many patients don’t think to mention them when they fill a prescription.

This latest study underscores the critical importance of keeping a list of all the medicines you take regularly, including prescription and over-the-counter drugs, vitamin/mineral combinations, and herbal supplements. All health care providers, including your doctor, dentist and pharmacist, should know the full list of medicine you take. And if you develop symptoms after starting a new medicine or supplement, see your doctor immediately.

©2009 PDQhealth

Tags: drug interactions, supplement interactions