SPL Set ID: 3ac203a2-4c55-deac-e063-6394a90aa165

The active ingredient in alosetron tablets, USP is alosetron hydrochloride (HCl) USP, a potent and selective antagonist of the serotonin 5-HT 3 receptor type. Chemically, alosetron is designated as 2,3,4,5-tetrahydro-5-methyl-2-[(5-methyl-1H-imidazol-4-yl)methyl]-1H-pyrido[4,3-b]indol-1-one, monohydrochloride. Alosetron is achiral and has the molecular formula C 17 H 18 N 4 O•HCl, representing a molecular weight of 330.81 g/mol. Alosetron is a white to pale brown color powder that has a solubility of 70.5 mg/mL in DI Water, 45.7 mg/mL in 0.1 N HCl, 79.4 mg/mL in pH 4.5 Acetate Buffer, 3.2 mg/mL in pH 6.8 Phosphate Buffer and 0.1 mg/mL in pH 7.5 Phosphate Buffer. The chemical structure of alosetron is: Alosetron tablets, USP are supplied for oral administration as 0.5 mg (white) and 1 mg (light blue) tablets. The 0.5 mg tablet contains 0.562 mg alosetron hydrochloride, USP equivalent to 0.5 mg alosetron and the 1 mg tablet contains 1.124 mg alosetron hydrochloride, USP equivalent to 1 mg of alosetron. Each tablet also contains the inactive ingredients lactose anhydrous, magnesium stearate, microcrystalline cellulose and pregelatinized starch (maize). The white film coat for the 0.5 mg tablet contains hypromellose, polyethylene glycol, polysorbate 80 and titanium dioxide. The light blue film coat for the 1 mg tablet contains FD&C blue #2, hypromellose, macrogol, polysorbate 80 and titanium dioxide. 1