A University of Michigan study, published in the journal Academic Emergency Medicine, found nearly 19.5 million older patients, or 16.8 percent of eligible emergency visits from 2000-2006, received one or more potentially inappropriate medications. Pain relievers and antihistamines -- sometimes used as a sedative or anti-allergic -- are among the most common drugs used in emergency visits.
Dr. William J. Meurer, an assistant professor at the University of Michigan, said the large sample of approximately 470,000 emergency department and outpatient clinic visits, corresponding to a national estimate of about 1.5 billion total visits, allowed the researchers to determine the extent of the problem nationwide.
Potentially inappropriate medications are less likely to occur in visits to hospitals in the Northeast and twice as likely in other parts of the country, the study said. Receiving a potentially inappropriate medication was more likely to occur at for-profit hospitals, the researchers said.
Ten medications accounted for 86.5 percent of potentially inappropriate medications used in the emergency room. The five most common ones were promethazine, ketorolac, propoxyphene, meperidine and diphenhydramine.
The study did not explore the possibility of medication interactions, so it is possible the potential harm by medications is underestimated, the researchers said.