Antibiotics in Food Animals: FAQ
Jan. 6, 2012 -- Food animals get 80% of the antibiotics used in the U.S. -- mostly in ways that can lead to the growth of drug-resistant superbugs.
Emerging drug resistance in bacteria is one of the world's greatest health threats, according to the CDC, the FDA, the World Health Organization, and a wide range of medical professional societies.
These groups cite "strong evidence" that many of these hard-to-treat germs arise in food animals and spread to humans. For this reason, the FDA argues strongly against unwise -- "injudicious" -- use of antibiotics in livestock. Yet over 80% of animal antibiotics are used in these ways.
In January 2012, the FDA prohibited some uses of the cephalosporin class of antibiotics in food animals. But these antibiotics make up less than a fraction of 1% of the 15,000 tons of antibiotics used in U.S. food animals each year.
This raises important questions. Here are WebMD's answers.
Why are antibiotics used in food animals?
There are two main reasons: To promote animal health, and to make animals grow faster.
The FDA has no problem with the antibiotics used to treat disease in animals. And it has no problem with antibiotics used under the direct supervision of a veterinarian who is treating specific animals.
But over 80% of antibiotics used in food animals is put into their feed or water by livestock producers, almost always on a herd-wide basis. This makes animals put on weight faster even if they don't eat more food.
Such "production use" of antibiotics is what the FDA, in its June 2010 guidance to the industry, deemed unwise or "injudicious."
How can antibiotics given to animals create drug-resistant germs?
If you get an antibiotic prescription from your doctor, you'll be warned to take every single one of the pills exactly as prescribed. That's because the last few pills mop up the most drug-resistant germs. If you take too low a dose, the most resistant germs remain.
The same thing happens in animals. Veterinarians treat sick animals with appropriate doses of antibiotics.
But when antibiotics are used to make animals grow faster, they are given at low doses over long periods of time. That's a recipe for growing drug resistant bacteria in food animals.