In order to gain cheap and quick access to antibiotics, Americans may be taking medications that are intended to treat fish, a new study has found.

As Ed Cara reports for Gizmodo, the disconcerting research was presented recently at a clinical meeting of the American Society of Health-System Pharmacists (ASHP), meaning the results have not yeat been peer-reviewed. A team based out of the University of South Carolina College of Pharmacy investigated the online fish antibiotic market and looked at customer reviews and comments on websites that sell fish antibiotics in the United States.

Out of the 2,288 comments reviewed by the team, 55 indicated that the antibiotics had been ingested by humans. It’s not a huge proportion—just 2.4 percent—but those 55 comments received a high degree of engagement, garnering nine times more “likes” and “dislikes” than the fish-related posts. Responding to a question online, one vendor assured customers that the fish antibiotics were safe for human use. But this, experts say, is not the case.

“While human consumption of fish antibiotics is likely low, any consumption by humans of antibiotics intended for animals is alarming,” says study co-author Brandon Bookstaver.

When fish are under the weather, they can be treated with antibiotic pills, which are popped into their tanks and absorbed through the skin. Ailing fish are often given the same antibiotics—amoxicillin, ciprofloxacin, penicillin—that humans take, Maya Wei-Haas reported for Smithsonian in 2017. In fact, the study authors found that five antibiotics marketed for fish have the same imprints, color, and shape of products marketed to humans.

But unlike antibiotics for humans—or even for animals like cats, dogs, and livestock—fish antibiotics are “completely unregulated by the Food and Drug Administration,” explains Michael Ganio, ASHP director of pharmacy practice and quality. People can buy these pills over the counter, without a prescription, and they can be relatively cheap. The researchers “found a bottle of 30 capsules of 500 milligram amoxicillin sold for $8.99,” Cara reports, “while the same quantity might run as high as $32 at Rite Aid at retail price, according to a search on GoodRX.”

And then there is the cost of a doctor’s visit, which, for someone without insurance, can be high.

Though it may make them easier to access, the unregulated nature of fish antibiotics is highly problematic, experts say. “The FDA does not have any information about the unapproved antibiotics sold in pet stores because they have not been evaluated for quality, safety, effectiveness, or purity,” the agency said in a statement to Haas in 2017. “We strongly advise people to not substitute them for approved products that are intended for use in humans as prescribed by their health care provider.”

It’s not just the medications themselves that are a problem; it can be dangerous to self-diagnose. Antibiotics are only effective against bacterial infections. They do not fight off viral infections, and taking antibiotics when you don’t need them can lead to bacterial resistance. Additionally, as Wei-Haas points out, “[e]ven broad spectrum antibiotics work differently to target different kinds of infections.” A doctor is needed to identify the illness and make sure the patient is getting the appropriate treatment.

Of course, desperation is likely a factor that drives people to buy fish antibiotics online instead of following the standard channels of medical diagnosis. More than 27 million people in the United States did not have health insurance coverage in 2018, and costs of pharmaceuticals are rising.

“Humans taking fish antibiotics doesn’t seem to be a specific problem that can be addressed with a specific solution or single law like one increasing the regulation of fish antibiotics,” Farzon Nahvi, an emergency room doctor in New York City, tells Jessica Glenza of the Guardian. “This simply seems to be a symptom of the much larger issue of a broken healthcare system, where people who are excluded from the system are looking for solutions outside of it, sometimes to dangerous effect.”