Table 2. Clinical utility of agonists and antagonists associated with 5-HT metabolism in gastrointestinal disorders.

Target	Mechanism	Potential and documented clinical utility
5-HT1 receptor family	Agonist	FD; IBS-D
	Antagonist	FD; IBS; GERD
5-HT2 receptor family	Agonist	None
	Antagonist	IBS-D (women only)
5-HT3 receptor	Agonist	GERD; constipation-predominant IBS
	Antagonist	IBS-D; FD; nocturnal GERD; chemotherapy-induced nausea and vomiting; radiation induced nausea and vomiting; post-operative vomiting
5-HT4 receptor	Agonist	Chronic constipation; gastroparesis; GERD; IBS-C; IBS-M; FD
	Antagonist	GERD
5-HT7 receptor	Agonist	No known applications in GI disorders, however, receptor is thought to mediate colonic relaxation, therefore a potential role in functional GI disorders
	Antagonist

Abbreviations: FD, functional dyspepsia; GI, gastrointestinal; IBS-C, constipation-predominant irritable bowel syndrome; IBS-M, mixed IBS; GERD, gastroesophageal reflux disease; IBS-D, diarrhea-predominant IBS; 5-HT, 5-hydroxytryptamine.

Table adapted from references 58,79,80,81,82,83,84,85,86 as well as company websites and FDA.gov.