I agree with the others...that another visit to the vet is probably best. It could be they missed something. Some parasites can be missed and some are hard to find in the stool sample.
Your babies problems sound much like what I went through with Maddie when she was younger. She would be on flagyl and shortly after finishing up the meds, she'd get it again. My vet diagnosed her with Irritable Bowel Syndrome and put her back on flagyl for a time, and then had me very slowly wean her off the med. That worked and she didn't get the diarrhea back.
Hope your sweetie is feeling better soon! |