WASHINGTON — In an effort to limit the further development of antibiotic resistant bacteria, the Food and Drug Administration is initiating a plan to phase out the use of what it terms “medically important antimicrobials” in food production animals to enhance growth and improve feed efficiency.

In a final guidance issued Dec. 11, the F.D.A. laid out a plan for animal pharmaceutical companies to voluntarily revise the F.D.A.-approved use conditions on the labels of products to remove such production indications as “growth promoting,” etc. The plan also calls for changing the current over-the-counter status to bring the remaining appropriate therapeutic uses under veterinary oversight and requiring a prescription for use.

Once a manufacturer voluntarily makes the changes, its medically important antimicrobial drugs may no longer be used for animal production purposes, and their use to treat, control, or prevent disease in animals will require a prescription.

The F.D.A. said it is asking animal pharmaceutical companies to notify the agency of their intent to sign on to the strategy within the next three months. The companies would then have a three-year transition period to implement the changes.

“Implementing this strategy is an important step forward in addressing antimicrobial resistance,” said Michael Taylor, F.D.A. deputy commissioner for food and veterinary medicine. “The F.D.A. is leveraging the cooperation of the pharmaceutical industry to voluntarily make these changes because we believe this approach is the fastest way to achieve our goal. Based on our outreach, we have every reason to believe that animal pharmaceutical companies will support us in this effort.”

In 2010, the F.D.A. called for a strategy to phase out production use of medically important antimicrobial products and to bring the remaining therapeutic uses in animals under the oversight of a veterinarian. The guidance document the F.D.A. issued on Dec. 11, which was previously issued in draft form in 2012, lays out such a strategy and marks the beginning of the formal implementation period.

The American Meat Institute, Arlington, Va., expressed support for the F.D.A.’s proposal.

“A.M.I. strongly supports the prudent and judicious use of antibiotics in food animal production under the care of a veterinarian, as defined by the American Veterinary Medical Association, which is consistent with protecting both animal and public health, ensuring the ability to medically treat animals, and maintaining the highest standard of animal welfare practices and we believe guidance 213 adheres to these principles,” the trade association said in a statement. “A.M.I. is committed to working with the F.D.A. over the next three years as this guidance is implemented and beyond with research for therapeutic options and further understanding how resistance is developed and transmitted among humans, animals, and other living organisms.” 

This past September, the Centers for Disease Control and Prevention recommended several steps to slow the development of antibiotic resistant bacteria. Recommendations made by the C.D.C. included only use antibiotics to treat disease. Another step the agency offered for consideration would be to put a tracking program in place to gather data on antibiotic-resistant infections and the causes of the infections. From such an effort, the C.D.C. said strategies may be developed to lessen the spread of antibiotic resistant bacteria.