Lisa,
 
The best thing for you and for Otis is to take your vet's advice and
either trust him or find a vet that you do trust.  Since you don't have
the medical training that a vet does, making your own decisions about a
course of medical treatment is not wise.  If you truly don't trust this
vet, you should find one that you do trust.
 
Each patient is an individual with unique needs, and what has worked or
not worked for someone else's ferret may not apply to Otis's situation.
Only a vet who has made a personal examination of Otis is in a position
to judge what is best for him and his individual needs.
 
I hope this is helpful.
 
Nancy and critters
[Posted in FML issue 3756]