Suggest Treatment For Diarrhea With No Fever And Vomiting

My 6 yr old has has loose stools for 2 days. When he toots there is a small amount of mucus on his underwear. Pharmacist suggested it is just a stomach virus and to feed him fibrous foods like bread & crackers until it passes. No pain, no fever, no vomitting. Not even diarrhea, just very, very loose stools twice a day for the last 2 days...