SPL Set ID: 6fbb9ca2-e8ca-45c7-a178-b4c8dd7a9a1f

Doxazosin mesylate is a quinazoline compound that is a selective inhibitor of the alpha 1 subtype of alpha adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4 benzodioxan-2-ylcarbonyl)piperazine methanesulfonate. The empirical formula for doxazosin mesylate is C 23 H 25 N 5 O 5 • CH 4 O 3 S and the molecular weight is 547.6. It has the following structure: Doxazosin mesylate, USP is white to off white powder. It is freely soluble in formic acid; very slightly soluble in methanol and in water. Doxazosin is available as tablets for oral use and contains 1 mg (white), 2 mg (pink), 4 mg (pink) and 8 mg (purple) of doxazosin as the free base. Each doxazosin tablet, USP for oral administration contains 1 mg or 2 mg or 4 mg or 8 mg of doxazosin as 1.213 mg or 2.426 mg or 4.852 mg or 9.703 mg of doxazosin mesylate, respectively and inactive ingredients: lactose monohydrate, magnesium stearate, microcrystalline cellulose, sodium starch glycolate (botanical source: potato) and sodium lauryl sulphate. Additionally 8 mg tablet contains FD&C red #40 aluminum lake, FD&C blue #2 aluminum lake and 2 mg and 4 mg tablet contains ferric oxide red. Doxazosin Tablets, USP