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In an effort to help address potential antimicrobial resistance concerns in humans, the U.S. Food and Drug Administration issued guidelines to extend veterinary oversight and phase out the sub-therapeutic use of antibiotics that are important to human medicine in food producing animals for growth promotion purposes. The new guidelines will be implemented over a three-year transition phase.

Historically, certain antibiotics have been used in the feed or drinking water of food producing animals for production purposes. Some of these antimicrobials are also used to treat human infection, thus prompting concerns about the potential contribution of this practice affecting antimicrobial resistance. Guidance 213 calls for animal pharmaceutical companies to voluntarily revise the FDA-approved labels for these products to remove growth promotion labels. FDA also proposes to change Veterinary Feed Directive regulations to move the over-the-counter status of the remaining appropriate therapeutic uses to require veterinary oversight when used to treat, control, or prevent health issues in animals.