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Short answer Living with alosetron: what to watch for Common questions Related questions Sources**The most common side effect of alosetron is constipation, and its most serious risks are ischemic colitis and complications of severe constipation such as bowel obstruction or perforation.**
Your risk depends on your dose, how long you take the drug, and your bowel history, including any past constipation, Crohn disease, ulcerative colitis, diverticulitis, or clotting problems. Alosetron is approved only for women with severe diarrhea-predominant IBS who did not improve with other treatment, so it is not used for mild symptoms or in men. Most people start at the lowest dose twice daily, and the dose goes up only if diarrhea is still uncontrolled after four weeks. Milder effects such as abdominal pain, nausea, gas, and headache are more common than the serious ones. Drinking enough fluid and reporting any slowing of your bowels early are the two habits that keep a side effect from becoming an emergency.
Living with alosetron: what to watch for
Common questions
What are the side effects of Alosetron?
Alosetron (Lotronex) treats severe diarrhea-predominant IBS in women who have not responded to other treatment. Constipation is the most common side effect and can progress to bowel obstruction, perforation, or toxic megacolon. The other major risk is ischemic colitis, meaning reduced blood flow to the colon. Milder effects include abdominal pain, nausea, gas, and headache. Stop alosetron and contact your doctor right away if you become constipated or have new or worsening stomach pain or blood in your stool. Because of these risks, alosetron is prescribed in the US under an FDA safety program, and your prescriber should review your bowel history before you start.