alosetron, Lotronex (cont.)

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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).

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.

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.

DRUG INTERACTIONS: Fluvoxamine (Luvox) increases blood levels of alosetron by reducing its breakdown by the liver. Therefore, both drugs should not be combined. Ketoconzole, clarithromycin (Biaxin), itraconazole (Sporanox), and voriconzole (vfend) may also increase blood levels of alosetron.

PREGNANCY: There are no studies of alosetron in pregnant women. Therefore, it should be used cautiously during pregnancy.

NURSING MOTHERS: It is not known if alosetron is excreted in breast milk. Therefore, it should be used cautiously by nursing mothers.

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