FDA Fixes Label on Heparin due to Dosing Errors

December 5, 2012 — After years of receiving reports of dosing errors due to a confusing label on heparin, a popular blood-thinning medication, the U.S. Food and Drug Administration (FDA) issued a Drug Safety Communication to announce that they will require manufacturers to fix the label. The revised label will clearly state the total strength of the medication, instead of only the strength of 1 milliliter (mL). Hopefully, this will reduce the risk of calculation errors that can cause under-doses of the drug.

The revised labels will be required by May 1, 2013 on bottles of “Heparin Lock Flush, USP” and “Heparin Sodium Injection, USP.” During the transition period, the FDA recommends that caregivers separate the current and revised versions of the drug. Furthermore, caregivers should use all of their current heparin before switching to the revised medication.

The problem is that heparin comes in a 10 mL bottle, but the giant bold-face text says “5,000 USP units per mL.” Many incidents have occurred when caregivers misunderstood the label to mean that it contains a total of 5,000 USP units.

The revised label will read “50,000 USP units per 10 mL (5,000 USP units per mL).”

Medication safety experts have been aware of this issue since 2003. In 2009, standard labeling practices were changed to require that the total strength of the medication feature prominently in bold-face text, instead of the dose per mL. No dosing errors have been reported on labels for medications that have been updated.

Heparin is a type of blood-thinning medication that is used to prevent blood clots. It is mostly used in people undergoing medical procedures (especially patients with long-term catheters) or medical conditions that carry a risk of blood clots. It is also used to prevent existing blood clots from getting any bigger.