Pharmacy computers don’t catch dangerous drug interactions

by Terry A. Rondberg, DC

Posted June 15, 2011

As of 2009, a total of 3.9 BILLION prescriptions for more than 24,000 different drugs were dispensed. The average number of retail prescriptions per person in the US was 12.6.

Given these numbers, it’s not surprising that many people leave the drug counter of their local pharmacy with pills that, when taken together, have harmful or even deadly side effects. It’s estimated that at least 20-25% of all patients are given prescriptions that pose dangers when taken together. According to the Centers for Disease Control (CDC), 27,658 unintentional drug deaths occurred in the United States in 2007 alone – most of them caused by prescription “medicines.”

To “solve” this problem, sophisticated computer programs called clinical decision support system software were developed to alert pharmacists to potential problems with drug interactions. However, a recent study conducted at the University Of Arizona College Of Pharmacy found that only 28% of pharmacies' clinical decision support software systems correctly identified potentially dangerous drug-drug interactions.

The study was conducted at 64 pharmacies across Arizona. Members of the research team tested the pharmacy software using a set of prescription orders for a standardized fictitious patient. The prescriptions consisted of 18 different medications that posed 13 clinically significant drug-drug interactions. Of the 64 pharmacies, just 18 correctly identified all of the eligible drug-drug interactions and non-interactions.

"These findings suggest that we have a fundamental problem with the way interactions are evaluated by drug knowledge databases," says Daniel Malone, PhD, UA professor of pharmacy and lead investigator on the study. "The weakness of these systems could lead to medication errors that might harm patients. Pharmacists should become familiar with how their computer system identifies drug interactions. Consumers should always inform their doctor and pharmacist about all medications and other therapies they are using. The risk of harm from dangerous combinations can be reduced when patients create and maintain a medication list."

A better approach would be to seek drug-free care or, at least, reduce the number of prescription and over-the-counter medications.

SOURCE: Journal of American Medical Informatics, 2011;18:32-37 doi:10.1136/jamia.2010.007609

(Dr. Terry A. Rondberg is founder and CEO of the World Chiropractic Alliance and publisher of The Chiropractic Journal. His reports on other health and wellness news appear on www.TerryARondberg.com and www.TerryRondberg.com.)