really this is something a vet should decide but it sounds like he needs an antibiotic probably Clavomox plus maybe something stronger for the diarrhea like Metronidazole or flagle (sp), which they hate but it usually works in a day or two. If you don't get to the cause of the diarrhea, it will come right back after you finish giving the anti-diarrhea meds - that is why I would suggest Amoxy or preferably Clavomox. It might be also be he has Coccidi, which is naturally in their system but can go haywire when in stress (and no telling what causes stress, someone looked at them crooked, someone got their favorite toy, someone won't let them into their favorite hammock but to them it is stress). In that case though chances are your other one would eventually come down with it too as it is "catching". Our preferred medication for diarrhea is what we call TEMPS (itÂ’s a broad spectrum that treats many causes including coccidi) -Sulfamethoxazole and Trimethoprim - they don't seem to mind it so much. These would be suggestions to ask your vet (these meds are by prescription/ or distributed by the vet only) to see what he/she thinks about it as we be no means are vets and even vets can't guess over the phone or in written questions what is wrong with a ferret. Also check on the Pepto as I am thinking they changed their formula a few years back and it has some stuff in it now not good for ferrets. Millie Sanders at Txferretrescue.org with Texas Ferret Lovers Rescue and connecting Foster homes and sanctuaries [Posted in FML 8080]