If you live in a rural area, the Tractor supple store has all kinds of anti-biotics and pills for live stock....When I had the farm the refrigerator looked like something from the doctors office....for example: penicillin used on cattle and other live stock is the same as your doctor uses...You just need the sterile needles and the dosage goes by weight...sulfa in pill form is also available. A lot of city folks aren’t aware of this source for storage...each bottle has an expiration date, but in a pinch that just means it has lost some of its potency...usually a bottle of 100ml of penicillin is good for a couple of years under refrigeration... I ordered all my stuff from a vet catalog. Any one that raises livestock has such things on hand...I box of 100 needles and syrings are not that expensive from a vet catalogue.....
My fridge use to be the same, back when I was dealing with a lot of critters. My vet was very good and made house calls to the city for our critters there, just like she did for our critters in pastures.
We once got a bill for 2 dogs, 2 catz and 47 assorted rabbits, bucks, mothers and babies for a house call.
It was about $50 and the dogs and catz all got shots and she gave me meds for a case of wry neck that had shown up in the rabbits.
Country vets are cool people.
/johnny