Oh my goodness, what a stressful situation for all involved.
What type of medicine is the vet prescribing? How old was Ozzy and what were the circumstances of his adoption? Was the shelter aware of his SA?
I really really wish I could help you because I know how much you love Ozzy and it would be awful to be facing such stress.
Hopefully someone else will be able to offer some guidance or advice. Perhaps even the shelter, if you were to call and tell them what was happening.
Good luck and keep us posted
