Each film-coated tablet contains sitagliptin phosphate monohydrate 64.25 mg and metformin HCl equivalent to: Sitagliptin 50 mg as free base and metformin HCl 500 mg (Janumet 50/500 mg), metformin HCl 850 mg (Janumet 50/850 mg) or metformin HCl 1000 mg (Janumet 50/1000 mg).
It also contains the following inactive ingredients: Microcrystalline cellulose, polyvinylpyrrolidone, sodium lauryl sulfate and sodium stearyl fumarate. In addition, the film coating contains the following inactive ingredients: Polyvinyl alcohol, polyethylene glycol, talc, titanium dioxide, red iron oxide and black iron oxide.
Janumet contains 2 oral antihyperglycemic drugs used in the management of type 2 diabetes: Sitagliptin phosphate and metformin HCl.
Sitagliptin phosphate is an orally-active inhibitor of the dipeptidyl peptidase-4 (DDP-4) enzyme. Sitagliptin is present in Janumet in the form of sitagliptin phosphate monohydrate. Sitagliptin phosphate monohydrate is 7-[(3R)-3-amino-1-oxo-4-(2, 4, 5-trifluorophenyl)butyl]-5, 6, 7, 8-tetrahydro-3-(trifluoromethyl)-1, 2, 4-triazolo[4, 3-a]pyrazine phosphate (1:1) monohydrate with an empirical formula of C16H15F6N5O·H3PO4·H2O and a molecular weight of 523.32.
Sitagliptin phosphate monohydrate is a white to off-white, crystalline, nonhygroscopic powder. It is soluble in water and N, N-dimethyl formamide; slightly soluble in methanol; very slightly soluble in ethanol, acetone and acetonitrile; and insoluble in isopropanol and isopropyl acetate.
Metformin HCl (N, N-dimethylimidodicarbonimidic diamide hydrochloride) is not chemically or pharmacologically related to any other classes of oral antihyperglycemic agents. Metformin HCl is a white to off-white crystalline compound with a molecular formula of C4H11N5·HCl and a molecular weight of 165.63. Metformin HCl is freely soluble in water and is practically insoluble in acetone, ether and chloroform. The pKa of metformin is 12.4. The pH of a 1% aqueous solution of metformin HCl is 6.68.