Alosetron

⛔ FDA Black Box Warning

WARNING: SERIOUS GASTROINTESTINAL ADVERSE REACTIONS Infrequent but serious gastrointestinal adverse reactions have been reported with the use of alosetron tablets. These events, including ischemic colitis and serious complications of constipation, have resulted in hospitalization, and rarely, blood transfusion, surgery, and death. Alosetron tablets are indicated only for women with severe diarrhea-predominant irritable bowel syndrome (IBS) who have not responded adequately to conventional therapy [see Indications and Usage (1)] . Alosetron tablets should be discontinued immediately in patients who develop constipation or symptoms of ischemic colitis. Patients should immediately report constipation or symptoms of ischemic colitis to their prescriber. Alosetron tablets should not be resumed in patients who develop ischemic colitis. Patients who have constipation should immediately contact their prescriber if the constipation does not resolve after alosetron tablets is discontinued. Patients with resolved constipation should resume alosetron tablets only on the advice of their treating prescriber [see Dosage and Administration (2.1) , Warnings and Precautions (5.1) , (5.2)]. WARNING: SERIOUS GASTROINTESTINAL ADVERSE REACTIONS See full prescribing information for complete boxed warning. Infrequent but serious gastrointestinal adverse reactions have been reported with the use of alosetron tablets. These events, including ischemic colitis and serious complications of constipation, have resulted in hospitalization and, rarely, blood transfusion, surgery, and death. Alosetron tablets are indicated only for women with severe diarrhea-predominant irritable bowel syndrome (IBS) who have not responded adequately to conventional therapy. ( 1 ) Discontinue alosetron tablets immediately in patients who develop constipation or symptoms of ischemic colitis. Do not resume alosetron tablets in patients who develop ischemic colitis. ( 2.1 , 5.1 , 5.2 )

Contraindications

4 CONTRAINDICATIONS Do not initiate in patients with constipation ( 4.1 ) History of chronic or severe constipation or sequelae from constipation; intestinal obstruction, stricture, toxic megacolon, gastrointestinal perforation, and/or adhesions; ischemic colitis; impaired intestinal circulation, thrombophlebitis, or hypercoagulable state; Crohn's disease or ulcerative colitis; diverticulitis; severe hepatic impairment ( 4.2 ) Concomitant use of fluvoxamine ( 4.3 ) 4.1 Constipation Alosetron tablets should not be initiated in patients with constipation [see Warnings and Precautions (5.1) ] . 4.2 History of Severe Bowel or Hepatic Disorders Alosetron tablets are contraindicated in patients with a history of the following: chronic or severe constipation or sequelae from constipation intestinal obstruction, stricture, toxic megacolon, gastrointestinal perforation and/or adhesions ischemic colitis, impaired intestinal circulation, thrombophlebitis, or hypercoagulable state Crohn's disease or ulcerative colitis diverticulitis severe hepatic impairment 4.3 Concomitant Use of Fluvoxamine Concomitant administration of alosetron tablets with fluvoxamine is contraindicated. Fluvoxamine, a known strong inhibitor of CYP1A2, has been shown to increase mean alosetron plasma concentrations (AUC) approximately 6-fold and prolong the half-life by approximately 3-fold [see Drug Interactions (7.1) ] .

Pregnancy & Breastfeeding

8.1 Pregnancy Risk Summary The available data with alosetron tablets use in pregnant women are insufficient to draw conclusions about any drug-associated risks for major birth defects, miscarriage, or adverse maternal or fetal outcomes. In animal reproduction studies, no adverse developmental effects were observed with oral administration of alosetron in rats and rabbits during organogenesis at doses 160 to 240 times, respectively, the recommended human dosage (see Data). The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and miscarriage is 15 to 20%, respectively. Data Animal Data No adverse developmental effects were observed with oral administration of alosetron during the period of organogenesis to pregnant rats at doses up to 40 mg/kg/day (about 160 times the recommended human dose based on body surface area) or to pregnant rabbits at doses up to 30 mg/kg/day (about 240 times the recommended daily human dose based on body surface area).