SPL Set ID: edefc932-d25d-4ead-b348-b3b6d9232091

Venlafaxine extended-release tablets are extended-release tablets for oral administration that contain venlafaxine hydrochloride USP, a structurally novel antidepressant. Venlafaxine hydrochloride is a selective serotonin and norepinephrine reuptake inhibitor (SNRI). It is designated 1-[(1 RS )-2-Dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride or (±)-1-[α-[(dimethylamino)methyl]-p-methoxybenzyl] cyclohexanol hydrochloride and has the empirical formula of C 17 H 27 NO 2 HCl. Its molecular weight is 313.9. The structural formula is shown below. Venlafaxine hydrochloride is a white or almost white powder freely soluble in methanol and water; soluble in anhydrous ethanol and slightly soluble or practically insoluble in acetone. Its octanol:water (0.2 M sodium chloride) partition coefficient is 0.43. Venlafaxine extended-release tablets are formulated as extended-release tablet for once-a-day oral administration. Venlafaxine extended-release tablets use osmotic pressure to deliver venlafaxine hydrochloride at a controlled rate over approximately 24 hours. The system, which resembles a conventional tablet in appearance, comprises an osmotically active core surrounded by a semipermeable membrane. The unitary tablet core is composed of the drug and excipients (including the osmotically active components). There is a precision-laser drilled orifice in the semipermeable membrane on the side of the tablet. In an aqueous environment, such as the gastrointestinal tract, water permeates through the membrane into the tablet core, causing the drug to dissolve and the osmotic components to expand. This expansion pushes the drug out through the orifice. The semipermeable membrane controls the rate at which water permeates into the tablet core, which in turn controls the rate of drug delivery. The controlled rate of drug delivery into the gastrointestinal lumen is thus independent of pH or gastrointestinal motility. The function of venlafaxine extended-release tablets depends on the existence of an osmotic gradient between the contents of the core and the fluid in the gastrointestinal tract. Since the osmotic gradient remains constant, drug delivery remains essentially constant. The biologically inert components of the tablet remain intact during gastrointestinal transit and are eliminated in the feces as an insoluble shell. Each extended-release tablet contains venlafaxine hydrochloride, USP equivalent to 37.5 mg, 75 mg, 150 mg, or 225 mg venlafaxine. Inactive ingredients consist of cellulose acetate, colloidal silicon dioxide, lactose monohydrate, magnesium stearate, mannitol, microcrystalline cellulose, opacode black ink (S-1-277001) (ferrosoferric oxide, propylene glycol and shellac), opadry white 03L580003 (hypromellose, propylene glycol, titanium dioxide and triacetin), polyethylene glycol, povidone. venlafaxine-struct