Alosetron, sold under the brand name Lotronex among others, is a 5-HT3 antagonist used for the management of severe diarrhea-predominant irritable bowel syndrome (IBS) in women only. It was patented in 1987 and approved for medical use in 2002. It is currently marketed by Prometheus Laboratories Inc. (San Diego). Alosetron was withdrawn from the market in 2000 owing to the occurrence of serious life-threatening gastrointestinal adverse effects, but was reintroduced in 2002 with availability and use restricted. Medical uses
Alosetron is indicated only for women with severe diarrhea-predominant irritable bowel syndrome (IBS-D) who have: 

chronic IBS symptoms (generally lasting 6 months or longer),
had anatomic or biochemical abnormalities of the gastrointestinal tract excluded, and
not responded adequately to conventional therapy.Severe IBS-D includes: diarrhea and 1 or more of the following:

frequent and severe abdominal pain/discomfort,
frequent bowel urgency or fecal incontinence,
disability or restriction of daily activities due to IBS. Efficacy
The phase III trial for approval was published in 2000 as an industry-funded randomised, placebo-controlled trial (PCT). Its authors found 1 mg alosetron, taken orally twice daily for 12 weeks, was associated with a 12% (CI 4.7-19.2) improvement in relief from abdominal pain and discomfort associated with diarrhoea-predominant patients. The prescription of alosetron is currently approved in the U.S. at 0.5 and 1 mg.The FDA Medical Officers Review, dated November 4, 1999, noted: "Patients considered by investigators to fit the diarrhea-predominant subtype had at baseline... stool consistency values that were neither loose nor watery".
While death is rare among MAC patients, it can occasionally metastasize to local lymph nodes. The 10 year overall survival rate is 86.4%, however this is exceedingly close to many 10 year survival rates of populations without MACs present. Causes
Little is known about the causes of MACs, although some evidence has shown that ultraviolet light, radiation, and genes may be causation factors. A genetic role might also be plausible, according to some studies. In several cases, patients developed a MAC after immunosuppression. Treatment
Due to the invasive nature of MACs, most cases are treated with wide local excision in order to decrease the rate of reoccurrence. Increasingly however, Mohs micrographic surgery is being employed as it allows more specific margins to be removed, along with decreasing the size of postoperative scars and disfigurement. In rare cases, tumors can be deemed inoperable due to their size and location under vital structures of the face. Chemotherapy and radiation treatment have been used when metastasis has occurred or when an excision cannot be performed, but results have been inconclusive about their effectiveness. In some cases, radiation therapy has been shown to increase tumor size. While in other cases, it implies that it will decrease the success of the tumor regrowing. Long term follow-up is necessary, as some cases of local recurrence have been documented 30 years after the original diagnosis. See also
Syringofibroadenoma
Skin lesion
List of cutaneous conditions


== References ==