What is alosetron?
Alosetron blocks the action of a chemical called serotonin in the intestines. This slows the movement of stools (bowel movements) through the intestines.
Alosetron is used to treat severe, chronic irritable bowel syndrome (IBS) in women who have had diarrhea as the main symptom for at least 6 months. Alosetron should be used only in women who have tried other IBS treatments without success. Alosetron has not been shown to be effective in men with IBS.
Alosetron is available only under a special program called the Prometheus Prescribing Program. You must be registered in the program and sign documents stating that you understand the risks and benefits of taking this medication.
Alosetron may also be used for purposes not listed in this medication guide.
What is the most important information I should know about alosetron?
Alosetron is available only under a special program called the Prometheus Prescribing Program. You must be registered in the program and sign documents stating that you understand the risks and benefits of taking this medication.
Do not start taking alosetron if you are constipated. If you have constipation while taking alosetron, stop taking the medication and call your doctor right away.
Serious or fatal side effects on the stomach and intestines have occurred in some people taking alosetron. In rare cases, alosetron has caused severe constipation, or ischemic colitis (caused by reduced blood flow to the intestines).
Stop taking alosetron and call your doctor right away if you develop new or worsening constipation, stomach pain, bloody diarrhea, or blood in your stools (bowel movements). If constipation does not improve or if it gets worse, do not start taking alosetron again until you talk to your doctor.
Alosetron does not improve the symptoms of IBS for everyone. When alosetron does work well, it helps reduce stomach pain and discomfort, bowel urgency, and diarrhea. Some or all symptoms may improve within one to two weeks of treatment.
Stop taking alosetron if your IBS symptoms do not improve after 4 weeks of treatment. If you stop taking alosetron, do not start taking it again without your doctor's advice.
What should I discuss with my healthcare provider before taking alosetron?
Do not use alosetron if you have:
constipation (especially if it is your main IBS symptom);
a history of severe or ongoing constipation;
obstruction or perforation of your intestines;
Crohn's disease, ulcerative colitis, or diverticulitis;
blood clots, or circulation problems affecting your intestines;
severe liver disease; or
if you are also taking fluvoxamine (Luvox) to treat obsessive-compulsive disorder.
Tell your doctor if you have ever had any of the conditions listed above.
Serious or fatal side effects on the stomach and intestines have occurred in some people taking alosetron. In rare cases, alosetron has caused severe constipation, or ischemic colitis (caused by reduced blood flow to the intestines).
Stop taking alosetron and call your doctor right away if you develop new or worsening constipation, stomach pain, bloody diarrhea, or blood in your stools (bowel movements). If constipation does not improve or if it gets worse, do not start taking alosetron again until you talk to your doctor.
FDA pregnancy category B. Alosetron is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.
It is not known whether alosetron passes into breast milk or if it could harm a nursing baby. Do not take alosetron without telling your doctor if you are breast-feeding a baby.
Older adults and those who are ill or debilitated may be more likely to have serious complications from constipation.
This medicine should not be given to a child younger than 18 years old.