Description
Diclofenac sodium is a benzeneacetic acid derivative, designated chemically as 2-[(2,6-dichlorophenyl)amino] benzeneacetic acid, monosodium salt. The structural formula is:
soluble in methanol, soluble in ethanol, sparingly soluble in water and practically insoluble in chloroform and in dilute acid. The n-octanol/water partition coefficient is 13.4 at pH 7.4 and 1545 at pH 5.2. Diclofenac sodium has a dissociation constant (pKa) of 4.0 ± 0.2 at 25°C in water.
Each enteric-coated tablet for oral administration contains 25 mg, 50 mg, or 75 mg of diclofenac sodium. In addition, each tablet contains the following inactive ingredients. Inactive ingredients: Black iron oxide, croscarmellose sodium, hydroxypropyl cellulose, hydroxypropyl methylcellulose, lactose (monohydrate), magnesium stearate, methacrylic acid copolymer, microcrystalline cellulose, polyethylene glycol, povidone, red iron oxide, and titanium dioxide. The 25 mg also contains: D and C Yellow #10 Aluminum Lake and pharmaceutical glaze shellac. The 50 mg also contains: Pharmaceutical glaze shellac and yellow iron oxide. The 75 mg also contains: carnauba wax, glycerol monostearate, shellac, and yellow iron oxide.