What is alosetron, and what is it used for?
Alosetron (brand name Lotronex) is a prescription medicine used to treat severe diarrhea-predominant irritable bowel syndrome (IBS-D) in adults under specific conditions. It is not for general IBS symptoms and is typically reserved for people whose symptoms have not responded to other treatments. [1]
How does alosetron work?
Alosetron is a serotonin (5-HT) receptor antagonist, which helps reduce bowel overactivity associated with IBS-D symptoms. [1]
Who should be prescribed alosetron?
Because of important safety risks, alosetron is generally used only for selected adults with severe IBS-D that meets prescribing criteria and who have not responded adequately to standard therapies. [1]
What are the main risks and side effects people worry about?
The best-known serious risk associated with alosetron is ischemic colitis (reduced blood flow to the colon). Another serious complication reported with this class of drug is severe constipation and, in some cases, related complications. Because of these risks, alosetron use is tightly controlled and requires stopping the drug if certain warning symptoms occur. [1]
How is alosetron taken, and what happens if symptoms improve?
Dosing is typically adjusted based on response and tolerance, and treatment may be paused or stopped if side effects occur or if symptoms resolve. The exact regimen depends on the prescribed plan and patient-specific risk factors. [1]
Is alosetron still available?
Alosetron has had periods of restricted availability and controlled prescribing requirements, reflecting the balance between symptom benefit and serious bowel-related risks. [1]
Where can I read the official labeling?
You can find full prescribing information (including contraindications, warnings, dosing, and monitoring guidance) through the FDA’s drug labeling materials for Lotronex/alosetron. [1]
Sources:
[1] https://www.accessdata.fda.gov/scripts/cder/daf/