As to having fish-flex, its a great idea. I dont know why more people, especially people injecting themselves do not have antibiotics on hand just for this very possibility.
Fish-flex is ok, sounds like he actually got a prescription for keflex which is the same antibiotic as fish-flex except for humans not a fish tank.
I went on vacation for a month a couple of years ago and bought the fish-flex, damn if I didnt get sick, and dammit more that it was not a bug that keflex would treat. Coughing til I saw stars after the first week wondering why it wasnt responding to the keflex until I got back and picked up zpack, gone in 3 days.
Now I have 10 zpacks of azithromycin on hand just in case I get a painful red injection site. Save the $$ of a doctors or Er visit and I have a high deductible.
Bought the human grade version for a little bit more than the fishflex about 60$ from 4rx and they mailed it from India, took 3 weeks.
But here's the thing, if I bought the same amount of 500mg tabs of azithromycin from drugstore.com its 400$.
I highly recommend just ordering some antibiotics to have on hand, just like people do if they see gyno symptoms they have something on hand to take just in case. 60$ and this is like 10 courses of zpack therapy, far cheaper than a doctor or er visit and no need to make up a story that you got hit by neighbor kid's errant blowdart