Lilly Updates Humulin R U-500 label to Prevent Errors

Some errors have occurred when healthcare providers have used a U-500 vial instead of a U-100 vial. The U-500 vial contains 20 mL versus 10 mL or 3 mL for U-100 vials. U-500 vials are marked with a band of diagonal brown stripes to distinguish it from the U-100 vial, which has no stripes. "U-500" is also highlighted in red on the label.

To prevent unnecessary errors, the prescribed dose of U-500 should always be expressed in actual units of U-500 along with corresponding markings on the syringe the patient is using (i.e., a U-100 insulin syringe or tuberculin syringe).

Many errors occur due to dosing confusion when U-500 doses are prescribed in units or volume corresponding to a U-100 syringe, or when the prescribed dose is administered without recognizing that the markings on the U-100 syringe do not directly correspond to U-500 doses. If U-100 insulin syringes are used, since their markings are in units and are designed and intended for use with the less concentrated U-100 insulin products, it is extremely important to explain the amount of Humulin R U-500 insulin to be administered in both the actual dose and with specification of "unit markings" on the U-100 syringe.

Instruct the patient to inform hospital or emergency department staff of the actual dose of U-500 prescribed, not the unit markings on the U-100 syringe in the event of a future hospitalization or visit to the emergency department. If tuberculin syringes are used, since their markings are in volume (mL), the actual amount of Humulin R U-500 should be explained in both actual dose and with specification of volume (mL).

Note from the Publisher: A helpful conversion chart is provided in this week's Tool for Your Practice, the Humulin-R 500 New Conversion Chart, and in the new package and should always be used when administering U-500 doses with U-100 insulin syringes or tuberculin syringes.

A change in U-500 labeling clarifies that clinical experience has shown it frequently has time action characteristics reflecting both prandial and basal activity. It takes effect within 30 minutes, has a peak similar to that observed with U-100 regular human insulin. The injection U-500, normally given 2-3 times a day, should be followed by a meal within approximately 30 minutes of administration.

Institute for Safe Medication Practices www.ismp.org