Why are antibiotics used in food animals?

Antibiotics are used in animals for the same reason as for people:  to treat and control diseases.  Protecting the health of animals helps to protect human health.  About 60% of diseases that impact humans come from animals, so the link between animal health and human health is strong.  Maintaining health among both populations is critical, according leading health organizations worldwide, including the World Health Organization and the U.S. Centers for Disease Control.

FDA also has approved the use of some antimicrobials for the promotion of growth in certain livestock and also poultry.  However, no matter whether antimicrobials are used to treat disease or to promote growth, FDA safeguards are in place to ensure safe food.

What safeguards are in place to ensure food is safe?

First, veterinarians oversee health decisions for farm animals, including the types and amounts of medicines that should be given for specific illnesses or conditions. Second, only medicines approved by FDA are administered to farm animals.  Third, FDA sets "withdrawal times" for any approved medicines, or the time it takes the medicine to sufficiently clear the animal's system before it is allowed to enter the food supply.  And last, government agencies (FDA and USDA) monitor and test the food supply to ensure meat and milk are safe.  For example, milk from the farm is tested multiple times between the farm and grocery store.  If violations are found, the milk is destroyed and the farmer is responsible for any financial loss.

How are antibiotics for animals regulated by the government?

FDA has responsibility for approving and regulating drugs, including antibiotics that are administered to animals that produce food.  For any proposed drug, extensive scientific studies that evaluate the efficacy and safety in animals, as well as on the safety for humans who consume food that comes from animals that receive the medication, must be submitted and evaluated by FDA.  The FDA then determines if the medicine is safe for animals and for people, and it imposes any necessary rules on how the medicine must be used to ensure this safety.

What is the FDA doing about antibiotics being used for promoting growth in farm animals?

FDA's Center for Veterinary Medicine (CVM) published a final guidance document in April 2012 to eliminate the use of antimicrobial drugs for growth promotion purposes.

The guidance proposes two principles aimed at proper and judicious use of antibiotics in food-producing animals. The first is that these medicines should only be used when they are needed to assure animal health. FDA does not consider the use of these medicines to promote growth as necessary for animal health, and believes this type of use should end. The second principle is that these medicines should only be used with veterinary oversight or consultation. According to FDA, veterinarians have the scientific and clinical training necessary to ensure that medically important antibiotics are used on the farm in a judicious and appropriate manner.

FDA and food and animal health stakeholders and pharmaceutical companies are working cooperatively to phase out growth promotion uses of antibiotics. FDA is in the process of defining a process by which these medicines could only be used in feed products for treatment, control and/or prevention of disease. As a result, these medically important antibiotics would require veterinary oversight. This means that a veterinarian would be involved in the decision to add antibiotics to animal feed.

Sources: Draft Guidance for Industry #209, Letter from FDA Acting Assistant Commissioner for Policy Leslie Kux to Andrew Maguire, Environmental Defense, November 7, 2011.

Is it required that veterinarians prescribe antibiotics for farm animals, like doctors do for people, or can farmers/producers buy these antibiotics over-the-counter without a prescription?  

Yes, a prescription from a veterinarian is required for most antibiotics given to farm animals. FDA always recommends to producers that livestock veterinarians be involved in decisions about giving antibiotics to farm animals.  FDA recently announced its proposal to require veterinary oversight or consultation whenever antibiotics are used in farm animals (see above).

Since the late 1980s, FDA has generally required a veterinarian’s prescription for all new injectable antibiotics, as well as a veterinarian’s involvement in diagnosing a farm animal’s disease condition. Prior to the late 1980s, FDA approved some injectable antibiotics, as well as antibiotics mixed into feed for over-the-counter use.  However, some in-feed antibiotics require a prescription under the “veterinary feed directive” regulations.

If farm animals receive antibiotics, does that put me at greater risk of getting an infection that is resistant to antibiotic treatments?

Experts recently reviewed all of the scientific literature on this subject and concluded that the extent to which antibiotic use on the farm contributes to increases in antibiotic resistance among bacteria that cause foodborne illnesses in people is unclear[1]. Moreover, the experts noted that extensive scientific studies confirm that people are most likely to get resistant infections as a result of their own use of antibiotics.   With regard to foodborne illnesses, fortunately for most healthy individuals, the vast majority of foodborne illnesses, including those caused by resistant bacteria, are not severe enough to require antibiotic treatment.  However, to help reduce potential risk, FDA's antibiotic approval process includes a specific process to determine if using that particular antibiotic increases the risk of resistance.  It also imposes, if deemed appropriate, conditions for use of the antibiotic that would impede resistance development.  Nevertheless, consumers should always follow recommendations to prevent the occurrence of foodborne diseases, such as frequent hand washing and cleaning of food preparation areas, and cooking foods to recommended temperatures.

Adapted in part from “Questions and Answers: Animal Antibiotics, Antimicrobial Resistance and Impact on Food Safety”, International Food Information Council, March 1, 2008.

[1] Doyle, et al, Institute of Food Technologists, Summary of Expert Report, “Antimicrobial Resistance: Implications for the Food System”, 2006.