SPL Set ID: 6ffff72c-8784-477b-8722-5434a19881a0

Montelukast sodium, the active ingredient in montelukast sodium tablets and montelukast sodium chewable tablets, is a selective and orally active leukotriene receptor antagonist that inhibits the cysteinyl leukotriene CysLT 1 receptor. Montelukast sodium is described chemically as [ R -( E )]-1-[[[1-[3-[2-(7-chloro-2­-quinolinyl)ethenyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid, monosodium salt. The molecular formula is C 35 H 35 ClNNaO 3 S, and its molecular weight is 608.18. The structural formula is: Montelukast sodium USP is a hygroscopic, optically active, off-white to pale yellow colored powder. Montelukast sodium is freely soluble in ethanol, methanol, and water and practically insoluble in acetonitrile. Each 10 mg film-coated montelukast sodium tablet USP contains 10.38 mg montelukast sodium USP, which is equivalent to 10 mg of montelukast, and the following inactive ingredients: carnauba wax, croscarmellose sodium, hydroxypropyl cellulose, hypromellose, iron oxide red, iron oxide yellow, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and titanium dioxide. Each 4 mg and 5 mg montelukast sodium chewable tablet USP contains 4.15 mg and 5.19 mg montelukast sodium USP, respectively, which are equivalent to 4 mg and 5 mg of montelukast, respectively. Both chewable tablets contain the following inactive ingredients: artificial cherry flavor, aspartame, croscarmellose sodium, ferric oxide, hydroxypropyl cellulose, magnesium stearate, mannitol, and microcrystalline cellulose. Chemical Structure