Promethazine Black Box Warning Added For Skin Damage and Gangrene

The FDA is requiring manufacturers of the anti-nausea drug promethazine, which is a generic version of Phenergan, to include a “black box” warning on the drug’s labels about the risk of severe tissue damage and gangrene if the drug is not administered correctly.

Promethazine is an injectable drug first approved in 1956, which is prescribed for treatment of nausea and vomiting. The new warning, which was announced by the FDA on September 16, indicates that the drug should only be administered into deep muscle, as opposed to injecting it under the skin or into veins, where it can leach out and damage surrounding tissue.

Improperly administered promethazine can lead to severe tissue damage, gangrene and possibly lead to the need for affected limbs to be amputated. The FDA warned that doctors who wish to administer the drug intravenously should limit the concentration and rate of administration and be certain that the intravenous line is functioning properly.

Phenergan (promethazine) was the subject of a prominent Supreme Court decision issued earlier this year involving a product liability lawsuit filed against Wyeth for failing to warn about the risk of promethazine problems. In that case, a jury awarded Diana Levine $6.7 million after she had her right arm amputated due to improperly administered Phenergan. In Wyeth v. Levine, Wyeth argued that FDA approval of Phenergan and its warning label should protect the company from liability for the failure to warn claim. However, the Supreme Court rejected the argument with a 6 to 3 vote.

Medical device manufacturers were able to win a victory in the Supreme Court’s decision in Riegel vs. Medtronic in 2008 using a similar argument that FDA approval preempts lawsuits against manufacturers. Congress is currently considering legislation, the Medical Device Safety Act of 2009, which would clarify that FDA approval of medical devices does not result in preemption.

Generic manufacturers will have 30 days to provide the FDA with black box warnings that fit the new FDA requirements for promethazine. The drug already carries a warning about tissue damage and the risk of gangrene, but they are not prominently displayed, and the new warnings will be at the top of labels and medication guides, surrounded by a black box.