The United States Pharmacopeial Convention (USP) has revised its current labeling standards for heparin sodium injections and heparin lock flush solutions to address safety concerns about the expression of the drugs’ strength. USP said in a press release that a misunderstanding of the expression of total strength on multidose product labels might cause errors that could lead to serious consequences to patients. According to USP, the change in labeling will mostly impact heparin multiple-dose vials.

The new standards, which go into effect on May 1, 2013, are addressed in the labeling sections of the Heparin Sodium Injection and Heparin Lock Flush Solution monographs in the United States Pharmacopeia/National Formulary (USP/NF). The monographs are being revised to comply with USP/NF General Chapter <1> Injections, which requires “that the label reflect strength per total volume as the primary expression of strength followed in close proximity by strength per mL.”

The revision addresses a 2010 letter from FDA to USP expressing concern that healthcare practitioners often misunderstood product labels with strength statements written as “mg per mL” as total drug content statements, which could lead to improper patient dosing. USP’s Safe Medication Use Expert Committee reviewed FDA’s concerns.

In the press release, Roger L. Williams, USP’s CEO, said, “USP is committed to developing standards that help to advance public health. It is our goal to ensure that USP standards aid practitioners in their delivery of quality care to patients. Particularly in light of the public health emergency involving adulterated heparin in 2008, USP and FDA are continuing to work closely together to help ensure that heparin delivery is as safe and accurate as possible.”

USP will post the official monographs in the “Official Text” section on its website on Jan. 25, 2013.