The FDA is asking animal pharmaceutical companies to notify the agency of their intent to sign on to the strategy within the next three months. These companies would then have a three-year transition process.
"We realize that these steps represent changes for veterinarians and animal producers, and we have been working -- and will continue to work -- to make this transition as seamless as possible," Dunham said.
Also Wednesday, FDA issued a proposed rule to update the existing regulations relating to Veterinary Feed Directive drugs.
The use of VFD drugs requires specific authorization by a licensed veterinarian using a process outlined in the agency's VFD regulations. The new proposed rule is intended to update the existing VFD process and expand veterinary oversight by clarifying and increasing flexibility for the distribution and use of VFD drugs.
Such updates to the VFD process will assist in the transition of OTC products to their new VFD status, FDA said.
Stricter regulation or elimination of antimicrobials for animal use has been discussed several times on Capitol Hill in the past several years; Reps. Henry Waxman, D-Calif., and Louise Slaughter, D-N.Y., have long pushed for legislation to provide more information on the amount and use of antibiotics and other antimicrobials given to animals raised for human consumption.
However, a Centers for Disease Control and Prevention report earlier this year indicated that the widest misuse of antibiotics occurs in hospitals, countering sentiment among critics of antibiotics in agriculture that farms using antibiotics to prevent or treat bacterial infections in animals are the primary driver behind advancing resistance.