SPL Set ID: 2f64ed95-03ea-41c7-959e-c2ddb5cf2dff

Prazosin hydrochloride capsules, USP a quinazoline derivative, is the first of a new chemical class of antihypertensives. It is the hydrochloride salt of 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-furoyl) piperazine and its structural formula is: Molecular formula is C 19 H 21 N 5 O 4 • HCl It is a white to tan powder, slightly soluble in water and methanol, very slightly soluble in alcohol, practically insoluble in chloroform and acetone and has a molecular weight of 419.87. Each capsule, for oral administration, contains prazosin hydrochloride, USP equivalent (as the polyhydrate) to 1 mg, 2 mg or 5 mg of prazosin. Inert ingredients in the formulations are: colloidal silicon dioxide, lactose monohydrate, magnesium stearate and microcrystalline cellulose. The empty gelatin capsules contain black iron oxide, gelatin, red iron oxide, titanium dioxide and yellow iron oxide. In addition, the 1 mg empty gelatin capsules contain D&C Yellow No. 10 and FD&C Green No. 3; the 2 mg empty gelatin capsules contain D&C Red No. 28, D&C Yellow No. 10, FD&C Blue No. 1 and FD&C Red No. 40; and the 5 mg empty gelatin capsules contain FD&C Blue No. 1. The imprinting ink also contains ammonium hydroxide, propylene glycol, shellac glaze, simethicone and titanium dioxide. Prazosin Hydrochloride Structural Formula