Letters of the law: VFD, Rx and OTC
Who decides which medications will require a veterinary feed directive (VFD), prescription (Rx) or be available over-the-counter (OTC)?
That’s in the hands of FDA or, more specifically, FDA’s Center for Veterinary Medicine.
VFD medications are antimicrobials deemed medically important to humans that are permitted for use in or on animal feed. As of January 2017, they will require a VFD from a licensed veterinarian for use in food animals. Product labels will clearly indicate which ones require a VFD.
If at least one VFD medication is in a combination — for instance, one medication in an approved combination is a VFD product and another is an OTC medication — a VFD is still required.
So when is a Rx needed? All medically important antimicrobials to be administered in the drinking water of food animals will require a prescription from a licensed veterinarian. This rule also kicks in January 2017.
No Rx will be required for OTC feed medications that are not considered medically important, such as bacitracin.
 #120 Guidance for Industry Small Entity Compliance Guide Veterinary Feed Directive Regulation Questions and Answers. FDA. http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/UCM052660.pdf Accessed December 15, 2015.
 Veterinary Feed Directive Requirements for Veterinarians. FDA. http://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/ucm455416.htm Accessed December 15, 2015.