Common Medication Pairs that Contribute to Wrong Drug Errors
There have been more than 13,000 reports submitted to PA-PSRS classified as “Medication Error, Wrong Drug.” Analysis of these reports found that 35.5% (4,617 reports) did not list the second drug involved in the event. Review of the remaining 64.5% (8,400 reports) determined that the most common pair of medications mentioned in these reports is morphine and hydromorphone (see this Advisory for an article discussing this pair of medications). The most commonly cited drug in reports of wrong drug errors is OXYcodone with acetaminophen (Percocet®), which has been confused with HYDROcodone with acetaminophen (Vicodin®, Norco®), acetaminophen with codeine (Tylenol No. 3), and OXYcodone without acetaminophen. The accompanying table lists the 25 most commonly cited pairs of medications involved in wrong drug errors submitted to PA-PSRS.
|Drug #1||Drug #2||Total |
|Percent of Applicable |
Wrong Drug Errors (n=8400)
|Novolog Mix 70/30||Novolin 70/30||75||0.9%|
|Total of Above||||1,948||23.1%|
There are many strategies organizations can implement that may help prevent medication errors due to confusion between drug names. As a first step, consider identifying the look-alike and sound-alike drug pairs that are most often involved in errors at your facility. Then, consider incorporating the following strategies to reduce the risk of errors with those medications:
Separating products with look-alike names on storage shelves, computer screens, and on any printed prescriber or stock order forms.
Building computer alerts notifying the prescriber, pharmacy, and nursing and affixing warning labels to products or storage areas as appropriate.
Advising staff and patients about the potential for confusion.
Using bold print to clearly distinguish letters which differ on product and storage bins labels with look-alike drug names. This strategy is commonly referred to as “tall man lettering” (e.g., chlorproMAZINE and chlorproPAMIDE).
PA-PSRS users can track medication errors associated with look-alike/sound-alike names. When entering medication error reports, Question 22, “System Factors Contributing to Medication Errors” allows users to indicate if drug name confusion played a role in medication errors during prescribing, preparation/dispensing, or administration.1
More importantly, when entering wrong drug events into PA-PSRS, entering both drug names (i.e., the one that was prescribed and the one that was or could have been administered) will enable users to track the name pairs that are a problem in their organizations.
- Pennsylvania Patient Safety Reporting System. Medication errors linked to drug name confusion. PA PSRS Patient Saf Advis 2004 Dec;1(4):7-8.