In the antimicrobial stewardship area, there are a number of things that would be so easy to address (the “low hanging fruit”) but have received surprisingly little attention. A prime example is human use of antibiotic products intended for use in animals that are purchased over-the-counter (OTC) or over-the internet, without a prescription.  Yes, this still occurs in some regions. Until a few years ago, even in Canada you could have bought a variety of antibiotics for fish in many pet stores (but not anymore). While the role of this blatant misuse of antibiotics in the emergence of antimicrobial resistance pales in comparison to many other issues,  it’s still an obvious item to address.

You might say “So what? Does it really matter if someone uses a fish antibiotic on themselves?

The answer is yes, because those antibiotics are the exact same drugs (in a slightly different form and packaging) as those used in people. That’s why people will sometimes buy antibiotics marketed for fish and give them to themselves, usually with dosing instructions from the internet. It’s exceptionally difficult to figure out how often this is done and how much harm is does.

A recent study in PlosOne (Zhang et al. 2020) looked at the availability of OTC antibiotics on internet sites from the US, and tried to infer information about purchase for self-medication. They did that by looking at comments and “likes” that the comments received on the websites.

  • Not surprisingly, a variety of medically-important antimicrobials were available for fish: amoxicillin cephalexin, metronidazole, ciprofloxacin, penicillin, clindamycin, doxycycline, erythromycin and trimethoprim-sulfa.
  • Overall 2.4% of comments and reviews for drugs on these sites were potentially associated with human use. Comments about human use received a lot more “likes” – 9.2 per review versus 0.5 per review not related to suspected human use.
  • The antibiotics that had the most human use-related reviews were erythromycin (8.3%), clindamycin (5%), ciprofloxacin (3.4%), penicillin (3.3%) and doxycycline (2.8%).
  • The greatest number of “likes” was for use of ciprofloxacin (ugh…).

While I assume there was some subjectivity determining what constituted human use, a few examples they provided were pretty clear, such as:

  • I don’t have health insurance and needed to get rid of an STD
  • Works just the same as pharmaceutical ciprofloxacin. No difference that I could tell. Will be getting more.
  • Since antibiotics are so difficult to find without a prescription, this is a great buy for human, animal and fish.

There is absolutely, positively no reason someone should be able to buy “animal” antibiotics over the counter, without medical advice.  Low hanging fruit need like this need to be picked from both regulatory  and enforcement standpoints.