In accordance with the final version of Industry Guidance Document #263 all antimicrobial drugs of medical importance, as defined, will only be available for administration under veterinary supervision, effective June 2023.  Antibiotics currently available as OTC formulations will move to prescription including injectable penicillins and oxytetracycline.

The guidance will apply to all animals and not only those intended for food production.  This means that companion species and backyard poultry will be subject to the same oversight.

The FDA is implementing Industry Guidance Document #263 as an extension of previous measures to prevent development of antimicrobial resistance.  The Food and Drug Administration recognizes "the expertise of veterinarians being critical to ensuring the responsible use of antibiotics in animals".