SPL Set ID: 313eab52-56fa-2a20-e063-6294a90a612f

The barbiturates are nonselective central nervous system (CNS) depressants primarily used as sedative-hypnotics. In subhypnotic doses, they are also used as anticonvulsants. The barbiturates and their sodium salts are subject to control under the Federal Controlled Substances Act. Phenobarbital is a barbituric acid derivative for oral administration and occurs as a white, odorless, slightly bitter powder that is soluble in chloroform, freely soluble in alcohol or ether, and slightly soluble in water. Its saturated solution has a pH of about 5.6. Chemically, it is 5-ethyl-5-phenylbarbituric acid with the molecular formula C 12 H 12 N 2 O 3 (232.24). The structural formula is as follows: Each Phenobarbital Tablet, USP contains 15 mg, 16.2 mg, 30 mg, 32.4 mg, 60 mg, 64.8 mg, 97.2 mg, or 100 mg of phenobarbital, USP. Inactive ingredients are as follows: Microcrystalline Cellulose; Lactose Monohydrate; Sodium Starch Glycolate, Type-A; Colloidal Silicon Dioxide; Magnesium Stearate