alosetron, Lotronex (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

PRESCRIBED FOR: Alosetron is approved for the treatment of severe diarrhea-predominant IBS among women who have chronic IBS symptoms lasting 6 months or longer and have not adequately responded to conventional IBS treatment.

Only prescribers who have enrolled in the Prometheus prescribing program for alosetron should prescribe alosetron due to safety reasons.

In two, 12-week studies involving over 1,200 women, most of whom suffered from diarrhea-predominant IBS, 40% of the patients (or 40 out of every 100 patients) had adequate relief from abdominal pain and discomfort while taking alosetron. Thirty percent of the patients (or 30 out of every 100 patients) had adequate relief while taking placebo (a dummy pill). In addition, among the alosetron-treated patients there were fewer bowel movements accompanied by a sense of urgency, fewer daily stools, and firmer stools than among the placebo-treated patients.

SIDE EFFECTS: The most common side effect with alosetron is constipation. One-quarter to one-third of patients may develop this side effect. Severe constipation or intestinal inflammation caused by poor circulation of blood (ischemic colitis) are rare but life-threatening, may require surgery, and may cause death. Therefore, alosetron must be discontinued immediately, and immediate medical attention should be sought if constipation or the signs of ischemic colitis (rectal bleeding or a sudden worsening of abdominal pain) occur.

Other important but less common side effects include:

GENERIC AVAILABLE: No

PRESCRIPTION: Yes

PREPARATIONS: Tablet: 0.5 and 1 mg.

STORAGE: Tablets should be stored at room temperature, 15 C to 30 C (59 F to 86 F).

DOSING: The starting dose is 0.5 mg twice daily. If constipation develops at this dose alosetron should be discontinued until the constipation resolves. It may be restarted at 0.5 mg once daily. If 0.5 mg once daily causes constipation, then alosetron should be discontinued. After 4 weeks, patients whose symptoms are not adequately controlled may receive up to 1 mg twice daily. Patients without adequate control after 4 weeks of treatment with 1 mg twice daily should discontinue alosetron. Alosetron may be taken with or without food.

Medically Reviewed by a Doctor on 6/11/2015


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