SPL Set ID: ee1fe3ac-7a2e-4133-90a2-1d8dc0552e74

The barbiturates are nonselective central nervous system (CNS) depressants that are primarily used as sedative-hypnotics. In sub hypnotic 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 and occurs as white, odorless, small crystals or crystalline powder that is very slightly soluble in water; soluble in alcohol, in either, and in solutions of fixed alkali hydroxides and carbonates; sparingly soluble in chloroform. Phenobarbital is 5-ethyl-5-phenylbarbituric acid and has the empirical formula C 12 H 12 N 2 O 3 . Its molecular weight is 232.24. It has the following structural formula: Phenobarbital is a substituted pyrimidine derivative in which the basic structure is barbituric acid, a substance that has no CNS activity. CNS activity is obtained by substituting alkyl, alkenyl, or aryl groups on the pyrimidine ring. Each 5 mL (teaspoon) contains 20 mg Phenobarbital and Alcohol 13.5%. The oral solution also contains Glycerin, Sucrose, FD&C Red #40, Orange Flavor and Purified Water.