Why would you use an antibiotic ointment when you're not infected yet? As a Microbiologist, I have to insist this is not good practice, and you couldn't buy the product over here over the counter because antibiotics are much more tightly regulated than in the US. It's not good for the natural bacteria you have down there, and not good for developing resistant strains.

I use a cream that is used for wounds and burns. it is basically Lanolin, plus Vitamin A and cod liver oil (believe it or not). It is extremely fatty and does not "sweat away". I used it the first time after I'd gotten completely raw on my behind and it healed up in 2 days. Smells a bit but it also contains vanillin to cover up the smell. Have to machine wash shorts afterwards.