SPL Set ID: b96ae7f1-7d4a-a211-e053-2995a90ab6e2

Tadalafil is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). Tadalafil has the molecular formula C 22 H 19 N 3 O 4 representing a molecular weight of 389.40. The structural formula is: The chemical designation is pyrazino[1′,2′:1,6]pyrido[3,4-b]indole-1,4-dione, 6-(1,3-benzodioxol-5-yl)-2,3,6,7,12,12a-hexahydro-2-methyl-, (6R,12aR)-. It is a crystalline solid that is practically insoluble in water, freely soluble in dimethyl sulfoxide, slightly soluble in methylene chloride. Tadalafil tablets USP, 2.5 mg, 5 mg, 10 mg and 20 mg are available for oral administration. Each tablet contains 2.5 mg, 5 mg, 10 mg, or 20 mg of tadalafil, USP and the following inactive ingredients: croscarmellose sodium, hydroxypropyl cellulose, hypromellose, iron oxide red (10 mg), iron oxide yellow (5 mg, 10 mg, 20 mg), lactose monohydrate, magnesium stearate, microcrystalline cellulose, sodium lauryl sulfate, talc, titanium dioxide and triacetin. 10