Back in 2012, the FDA banned “extra-label” non-medical use in animals for the cephalosporin class of antibiotics, which are commonly used to treat humans for pneumonia, urinary tract infections, and other maladies. Not only did this restriction fail to curb the use of cephalosporins, but a new FDA report shows that the drug use increased following the ban.

The report [PDF] shows that cephalosporin use in 2013 was at 28,337 kilograms, up from 27,654 kg the year before; an increase of nearly 2.5%.

Cephalosporins were not the only class of medically important drugs to increase in use in 2013. Tetracyclines, which are frequently used to treat bacterial infections and acne, are by far the most widely used drugs. In 2013, more than 6.5 million kg of tetracyclines were used on farm animals, an increase of 9% over the previous year.

In a recent Frontline report on antibiotics in farm animals, veterinary scientists in Texas explained that they had hoped to reduce the use of the more important cephalosporins by increasing the use of tetracyclines.

“We actually saw that resistance went up, which is not what we hypothesized,” said one researcher. “Our viewpoint historically has been that, sure tetracyclines aren’t that important for human health so why worry about them in animal agriculture? But they may be more important than we think, not because of their use in human medicine, but because they can expand resistance to critically important drugs.”

In all, livestock-related sales of antibiotics deemed medically important to humans were up 3% in 2013, to more than 10,100 tons, accounting for 70% of all medically important antibiotics sold in the U.S.

“Use of medically important antibiotics to produce meat and poultry is troubling,” writes Avinash Kar of the Natural Resources Defense Council, “because when the antibiotics are routinely given to herds and flocks of animals, some bacteria become resistant to the antibiotics. When these ‘superbugs’ multiply and spread, they threaten people’s health by contributing to the growing crisis of antibiotic resistance.”

According to the Centers for Disease Control and Prevention, more than 2 million people in the U.S. fall victim to drug-resistant pathogens every year, with some 20,000 dying as a result.

In late 2013, the FDA issued voluntarily guidelines for the drug industry, asking them to remove non-therapeutic uses — like growth-promotion — from approved uses of their livestock antibiotics. For the most part, the drug companies agreed, though some manufacturer continue to actively market the growth-promotion benefits of their antibiotics.

“The data released today shows us that use of human antibiotics on the farm has continued to rise, including the use of cephalosporins,” says Steve Roach, senior analyst for Keep Antibiotics Working. “This reaffirms just how timid FDA’s approach to addressing the problem of antibiotic overuse really is, and suggests that it may have limited impact.”

“This sobering assessment shows that FDA’s voluntary approach to reducing the use of antibiotics in meat production does not work,” said Dr. Michael Hansen, Senior Scientist for our colleagues at Consumers Union. “The bulk of the medically-important antibiotics used on farms (98%) are available over-the-counter without a veterinary prescription, for farmers to buy for whatever use they deem necessary.”

Given the time it takes for the FDA to put together these reports, we won’t have numbers for 2014 until sometime next year. That data will show whether the 2013 guidelines have had any impact on antibiotic use or if, as the drug industry itself predicted at the time, it won’t significantly change the numbers.

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