Table.

Treatment Outcomes of Drug for Irritable Bowel Syndrome Depending on Sex or Gender

Therapeutic target	Name	Dose	Mechanism of action	Effect of sex or gender
Loos stool (IBS-D)	Alosetron	0.5–1 mg peroral bid	5-HT3 receptor antagonist	Currently available to treat women with severe IBS-D. Initially demonstrated a significant improvement in women but not in men.97,98 Later, effective in both men and women.101,102
	Ondansetron	4–8 mg peroral every 8 hr	5-HT3 receptor antagonist	Did not conduct separate analyses by sex.106
	Cilansetron	2 mg peroral tid	5-HT3 receptor antagonist	Significant improvement in men compared to that in women.103
	Tegaserod		5-HT4 receptor agonist	Greater efficacy in women.103 Withdrawn from US market due to cardiovascular side effects.100
	Ramosetron	5 μg peroral daily 2.5 μg peroral daily	5-HT3 receptor antagonist	Initially limited to men with IBS-D.107,108 Now: a half-dose is prescribed for women.109,110
	Bile acid (Colesevelam)	1.875 g peroral bid	Decreased stool transit times	Limited data16
	Loperamide	4 mg peroral then 2 mg with each additional loose stool Maximum 16 mg/day	Binds gut wall opioid receptor Increases sphincter tone Decreased stool frequency	Limited data95
Hard stool (IBS-C)	Lubiprostone	8 μg peroral bid	ClC-2 activator	For IBS, approved for women ≥ 18 yr with IBS-C96,104 effective treatment of chronic idiopathic constipation in both men and women.96
	Linaclotide	290 μg peroral daily	Guanylate cyclase C receptor agonist	Efficacious in both men and women.115
	Eluxadoline	100 mg peroral bid	μ- and κ-opioid receptor agonist andδ-opioid receptor antagonist	Efficacious in both men and women.117,118 Contraindicated in patients with history of cholecystectomy.
Altered gut microbiota	Rifaximin	550 mg peroral tid for14 day	Presumed decrease in gas-producing bacteria	Did not conduct separate analyses by sex.91,105
Visceral hypersensitivity	Anti-depressant	TCAs Amitriptyline (10–59 mg), Imipramine (10–50 mg) Doxepin (10–59 mg), Nortriptyline (10–59 mg), Desipramine 10–200 mg	Various	Did not conduct separate analyses by sex.11,111
		SSRIs Citalopram, 10–40 mg fluoxetine, 10–40 mg paroxetine, 10–40 mg Escitalopram 10–40 mg Setaline 25–100 mg
		SNRIs Duloxetine 30–90 mg Venlafaxine 75–225 mg
Abdominal pain	Dicyclomine	20–40 mg peroral qid	Antagonizes acetyl-choline at muscarinic receptors, smooth muscle relaxer, inhibits bradykinin, reduces histamine induced spasm	Limited data11,117
	Hyoscyamine	0.125–0.25 mg peroral every 4 hr when necessary		Limited data11,113
	Peppermint oil capsule	0.2–0.4 mL tid	Smooth muscle relaxer; reduce gastric motility by acting on calcium channels (similar to dihydropyridine calcium antagonists)	Limited data11,113
Bloating	FODMAP		Decreases fermentable gas-producing foods	Limited data116,119
	Probiotics	Various	Repopulate the gut with more efficient bacteria	Limited data114
	Psychotherapy			Did not conduct separate analyses by sex.11,111,112

IBS-D, diarrhea-predominant IBS; IBS-C, constipation-predominant IBS; ClC-2, chloride channel-2; TCAs, tricyclic antidepressants; SSRIs, selective serotonin reuptake inhibitors; SNRIs, serotonin and norepinephrine reuptake inhibitors; FODMAP, fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; bid, twice a day; tid, 3 times a day; qid, 4 times a day.