Practitioners' Reporting News

Rapamune™ Packaging Leads to Practitioner Confusion and Errors

Issued July 25, 2001

Rapamune™ (Sirolimus) Oral Solution is an immunosuppressant agent manufactured by Wyeth-Ayerst. It is available in 1mL, 2mL and 5mL unit dose liquid packets. The concentration of all packet sizes is 1mg/mL. The USP Medication Errors Reporting (MER) Program has received seven reports since June 2000 describing the confusion and actual errors associated with the labeling of Rapamune.

Three reports noted that it is easy to confuse the various strengths of the product because the labels appear identical except for the total volume, which is displayed in small black print a few lines below the more prominently displayed strength indication, "1mg/mL."

The other four reports received detailed actual errors caused by this confusion. In those reports a total of six patients were actually given the wrong dose because practitioners failed to discern the total volume and mistook the prominently displayed "1mg/mL" for the actual size and strength of the packet. In one specific report, a 5-mg dose was ordered for a pediatric patient. To enable titration, it was requested that the pharmacy dispense 1-mg packets. The nurse instructed the patient's mother to give the child five of the 1-mg packets. The pharmacy, however, mistakenly dispensed the 5-mg packets, and the patient was given two doses that totaled 25 mg each. As a result of the error, the patient suffered gastric distress.

To help reduce errors related to the dispensing and administration of Rapamune (Sirolimus) Oral Solution, all staff should be informed of the potential confusion the labeling may cause. The National Coordinating Council for Medication Error Reporting and Prevention recommends that labels be read at least three times. For example, when preparing to dispense the medication, the label should be read when selecting the product, when packaging the product, and when returning the product to the shelf. At the point of care, the label should be read when reaching for or preparing the medication, immediately prior to administering the medication, and when discarding the used container or replacing the stock container in its storage location. The Council also recommends that signs or markers be used to help distinguish between different strengths of a medication.

Readers are advised that official USP cautions and warnings for drugs appear in the USP–NF or USP DI. Unless otherwise indicated, any advice or opinions expressed herein reflect solely the judgment of USP staff. Such statements are intended for further consideration and evaluation and may or may not be applicable to a particular practice. The USP Medication Errors Reporting Program is presented in cooperation with the Institute for Safe Medication Practices.