Alosetron is used to treat chronic irritable bowel syndrome in women who have had diarrhea for more than six months as a result of this disease. This drug works by blocking the production of serotonin in the intestines. It is only available to women who have tried other drugs for IBS without success.
Alosetron has not been shown to be effective in men and should not be prescribed for biologically male patients. In addition, it should only be prescribed to women whose major symptom is diarrhea, not women who suffer from constipation as a result of IBS.
The drug itself sometimes causes constipation, so it cannot be used in women who have constipation problems. In addition, in rare cases it causes a serious problem called ischemic colitis, in which the patient becomes so constipated that waste blocks blood flow to the intestines.