From a regulatory  standpoint, concern about antibiotic-resistant bacteria has been at the forefront of FDA’s agenda for 40 years or more. That has led to a change in regulatory policy and an ever-tightening regulatory environment.
In fact, in 1988, FDA declared that all new antibiotics  approved for use in food animals must be prescription only, according to Richard Carnevale, Animal Health Institute vice president of regulatory, scientific and international affairs. Since then, the drums have continued to sound for even more regulatory authority on the use of antibiotics in food animals.
“In the future, what do we expect to happen?” he asks. Of the four uses for antibiotics in food animals – treatment, prevention, control and growth – he expects cattlemen will be able to maintain the three that provide for therapeutic use . “However, growth promotion  uses will be limited to non-medically important antimicrobials as defined by FDA,” he says.
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He says FDA will phase out growth promotion use for older, medically important antibiotics over the next 3-5 years, depending on how quickly they can move on their regulatory timelines.
“The other thing I would speculate about, and this is speculation, are the other forms of medially important antimicrobials out there,” he says. “There are injectibles, there are boluses and tablets.” Some of those medically important compounds are still sold over the counter and FDA regulations and oversight isn’t as strict.
“So I expect, when FDA gets done with animal feeds, they’ll also take those medically important antibiotics that aren’t available by prescription or in other dosage forms, and put them under prescription. So a lot of those products that are now available in feed stores, like oxytetracycline, down the road won’t be available over the counter anymore.”
However, there’s no need to panic just yet – that prospect is quite a ways down the road. “FDA hasn’t proposed that yet,” he says. But he suspects that if FDA is going to phase out medically important antibiotics used for growth promotion , the next logical step is to tighten the availability of those products in other forms, even though they’re for therapeutic use.
In addition, that doesn’t mean all antibiotics will only be available from a veterinarian. “Take away ionophores, which are not used in human medicine, and 30% of the antibiotics used in animals are not used in human medicine,” he says.