In one report, a nurse who was taking a patient’s medication history recorded his insulin dose using the abbreviation “U” instead of writing the word “unit” (see Figure 1). Through the USP-ISMP Medication Errors Reporting Program (MERP), ISMP has also received a number of reports where patients have received overdoses of insulin or heparin when “U” for unit has been used. The order on the medication record was written as “5U” instead of “5 units.” A contributing factor to the insulin overdose identified by the institution was the use of “U” for units. In one example, an older male patient was ordered 5 units of Humalog (insulin lispro recombinant) but received 50 units of Humalog on two occasions. These errors often result in potential 10-fold or greater overdoses. One of the error-prone abbreviations most commonly reported to PA-PSRS is the abbreviation “U” used to indicate “units.” This abbreviation contributes to errors when it is misread as a zero (0) or as the number 4. Some of the common error-prone abbreviations involved in errors in PA-PSRS include: PA-PSRS has received over 200 reports describing situations in which the use of abbreviations has led to medication errors.
Abbreviations and nonstandard dose designations are frequently misinterpreted, and they often lead to errors resulting in patient harm.
However, some of these shortcuts can be very time-consuming for the person on the receiving end and can be dangerous to the patient. T hroughout healthcare, “shortcuts” such as abbreviations and symbols are often used to save time when communicating medication orders, especially in handwritten communication.