Recently, a patient at an Edmonton hospital was discharged with a new prescription for Lantus insulin, 8 units, to be injected subcutaneous every morning. The patient’s medication profile was used for the discharge prescription, which contained a handwritten, unacceptable abbreviation for units (incorrectly written as “U”). The prescription was then faxed to a community pharmacy. The community pharmacy filled the prescription as 80 units rather than 8 units, which resulted in the patient receiving ten times the prescribed dose of insulin. The community pharmacist mistakenly interpreted the notation “8U” as “80”.
U is an unacceptable abbreviation that should not be used. The standard terminology is to write out the word “units” to avoid this type of error. A listing of dangerous abbreviations like this one can be found at the ISMP website: https://www.ismp-canada.org/download/ISMPCanadaListOfDangerousAbbreviations.pdf
Another area of concern is that 80 units of insulin is not a routine dose. Had the community pharmacist questioned this unusually high dose more closely, this error may not have occurred.
Pharmacists are reminded about their responsibilities to always assess the appropriateness of prescriptions they dispense, even when the prescription’s source is a hospital. When potential drug related problems are identified, pharmacists must take steps to investigate and resolve these problems. These steps can include collaborating with the prescriber and chatting with the patient.
