FDA VFD medicated petfood

21 CFR 558 (Veterinary Feed Directive, VFD) regulates veterinary-prescribed medicated feeds including some pet foods. VFD drugs (currently 18 substances) include: avilamycin, chlortetracycline, decoquinate, florfenicol, lincomycin, neomycin, oxytetracycline, penicillin, sulfadimethoxine, tilmicosin. VFD pet food products are extremely limited because most VFD drugs are intended for livestock/poultry. The most common pet-relevant VFD application: sulfadimethoxine/albon (Pfizer) for coccidiosis treatment in puppies housed in breeding facilities. Pet owners can ONLY obtain VFD feeds via a licensed veterinarian's prescription — direct over-the-counter sale is prohibited. CFR 558.6 specifies the VFD drug label requirements: withdrawal period (for food-producing animals), target species, indications, dose, and caution statements.