The FDA Center for Veterinary Medicine has received reports indicating that flunixin meglumine is being prescribed or administered by an intramuscular route in cattle. Flunixin meglumine's only current approved route of administration in cattle is intravenous.

The FDA-CVM reports it is important for veterinarians to prescribe and use flunixin meglumine and other drugs for food animals according to directions on the label so that adulterating residues are avoided. The intramuscular administration of flunixin meglumine has the potential to cause violative drug residues, since it requires a longer withdrawal period to deplete the drug-related residue in the animal than does the approved intravenous route of administration.

It is considered extralabel use to administer an FDA-approved product through an unapproved route. The Animal Medicinal Drug Use Clarification Act limits extralabel drug use to treatment when the health of an animal is threatened or suffering or death may result from failure to treat. Yet the CVM has learned that flunixin meglumine is being administered intramuscularly for convenience.

Source: American Veterinary Medical Association