Many Patients at Risk of Harmful Drug Interactions

By Robin Hindery

Though the use of prescription and over-the-counter (OTC) drugs in the United States is rising, many patients fail to educate themselves about the medications they are taking — putting themselves at risk of harmful or even lethal drug interactions, according to researchers at UCSF and elsewhere. Drug information is readily available — on product labels, from pharmacists, on the Internet — but the majority of patients tend to ignore it, according to Bill Soller, PhD, executive director of the UCSF Center for Consumer Self Care and a health sciences clinical professor in the UCSF School of Pharmacy. “We know from our own research that more than 50 percent of patients say they never, seldom or only half the time read the drug information that is given to them with their medications,” he said, referring to a Journal of the American Pharmacists Association paper he co-authored with School of Pharmacy colleague James Lightwood, PhD, in 2007. “That is a big information gap.” Uninformed patients are needlessly putting themselves at risk, Soller said, and that risk threatens to grow as the country’s medicine cabinets become increasingly crowded. According to the Centers for Disease Control and Prevention’s National Center for Health Statistics, in 2004, nearly half of all Americans were taking at least one prescription medication, and one in six individuals was taking three or more. In a study published in the Dec. 24/31, 2008, issue of the Journal of the American Medical Association (JAMA), University of Chicago researchers interviewed roughly 3,000 individuals age 57 to 85 about their use of prescription and OTC drugs and dietary supplements, and found that one in 25 was potentially at risk of having a major drug-drug interaction. Soller, who has long advocated improved labeling of OTC drugs and supplements, said the JAMA study’s findings “don’t tell us anything we didn’t already know” about patients’ poor understanding of the many medications and supplements they regularly consume. To fill the knowledge gap, Soller urges patients — or their caregivers — to take an interest in drug labels and to check in regularly with their pharmacist, even if they think they are well-informed. “New information always develops over time, so what you learned three or four years ago when you started taking a medication may no longer be current,” Soller noted. “I think it’s a good practice to periodically ask your pharmacist, ‘Is there any recent information? What are the potential drug interactions I might experience?’ It takes less than a minute.” For those who prefer web-based interaction, the UCSF Center for Consumer Self Care offers a helpful tool. Since 2003, the center has provided the Ask the Pharmacist Service through Blue Shield of California. The service allows members of the not-for-profit health plan to submit online questions to UCSF pharmacists about prescription and OTC drugs. Ask the Pharmacist also answers queries about herbal and dietary supplements — products that can pose just as great a health threat as more traditional medications, Soller said. “Do not make an assumption that dietary supplements marketed as food are automatically safe,” he warned, noting that the Food and Drug Administration (FDA) does not require supplement makers to include information about potential drug interactions on their products’ labels. However, there are resources available for those seeking information about herbs and supplements, including the FDA’s own website and MedlinePlus. Soller cautioned that while it is important for patients to stay informed and up to date about their medications, a possible drug interaction does not mean a guaranteed drug interaction. “It’s like any side effect,” he said. “Just because there’s a potential doesn’t mean it’s going to occur.” Related Links: UCSF Center for Consumer Self Care Ask the Pharmacist Service Blue Shield of California (UCSF Pharmacists) Index to Drug-Specific Information US Food and Drug Administration MedlinePlus: Drugs, Supplements and Herbal Information National Library of Medicine and National Institutes of Health Use of Prescription and Over-the-Counter Medications and Dietary Supplements Among Older Adults in the United States JAMA (Dec. 24/31, 2008) 300(24):2867-2878