Clinical recommendation	Evidence rating	References	Comments
Probiotics may reduce the incidence of antibiotic-related diarrhea.	A	5–7, 9	Most validated products are Saccharomyces boulardii and Lactobacillus rhamnosus GG
Probiotics may reduce the duration and severity of all-cause infectious diarrhea.	A	5, 10–12	A large meta-analysis of all-cause infectious diarrhea included studies with viral diarrhea and traveler's diarrhea
Probiotics may reduce the severity of pain and bloating in patients with irritable bowel syndrome.	B	17–19	Small trials to date
Probiotics may reduce the incidence of atopic dermatitis in at-risk infants. There is preliminary support for treatment of symptoms.	B	20–23, 25–28	—