Table 1.

Irritable bowel syndrome subtypes

Subtype	Definition
	(symptoms classified using Bristol stool form scale)
IBS with constipation (IBS-C)	> 25% of stools are hard or lumpy and < 25% of stools are loose/mushy or watery
IBS with diarrhea (IBS-D)	> 25% of stools are loose/mushy or watery stools and < 25% are hard or lumpy
Mixed IBS (IBS-M)	> 25% of stools are loose/mushy or watery stools and > 25% and hard or lumpy
Unsubtyped IBS	insufficient abnormality of stool consistency to meet criteria for IBS-C, D, or M (in the absence of antidiarrheals or laxatives)

IBS: Irritable bowel syndrome.