ENROFLOXACIN is Baytril, Baytril is the trade name! So your ham is on the same antibiotics as all the other hamsters.
Heres some links to infomation about wet tail you could try:
http://www.petwebsite.com/hamsters/hamster_wet_tail.htm
http://www.vetbase.co.uk/information/we ... msters.php
http://www.britishhamsterassociation.or ... ilfact.htm
You could google "wet tail" for more websites.
My hamster currently has a secondry infection of the lungs, and he is also on baytril, i found that my Sammi was behaving normally, and seemed a healthy happy hamster, even after he coughed up some blood, hes still on baytril now and it seems to be improving sammis infection alot, so i hope you will see the same results.
I really doubt size effects how the are effected by wet tail, its more likley to be their age that effects this, but its best you see what others say as im not sure.
As you probably know hamsters have a very short lifespan, which means they can still live to their expected age if you take good care of them, but wet tail can kill at any point, but you should see his condition deteriorate before he passes away.
My best advice is i can give to you is to have a look at some infomation on the internet about wet tail, and make sure you keep him as comfy and as happy as possible, and enjoy the time you have left with him, he could still be around for a while yet!
Hope he pulls through