Probiotics for Diarrhea

Q: What's the best probiotic for a 5 month old maltese who is having Diarrhea? She had it about 6 weeks ago and our vet prescribed Flagyl (antibiotic) as well as a probiotic, but I wondered if there is a probiotic that I could just buy at Petco instead of having to go back to my vet's office. She just started having diarrhea again 3 days ago. Thanks, Sandra

A: There are many "probiotics" available over the counter. We use the Purina product Fortiflora. I have also used one from NaturVet and one called Probiotic Miracle. There are many causes of diarrhea in puppies and while using probiotics is not detrimental they may not address the primary cause so if the diarrhea persists for more than a couple days or if it is accompanied by other symptoms please let me know so I can advise.