SPL Set ID: feda8ef8-6d67-4ea1-bf19-21fd7d4872bd

The barbiturates are nonselective central nervous system (CNS) depressants that are 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 and occurs as white, odorless, small crystals or crystalline powder that is very slightly soluble in water; soluble in alcohol, in ether, 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. Phenobarbital Oral Solution, USP is red colored liquid with cherry flavor. Each 5 mL (teaspoon) contains 20 mg Phenobarbital and Alcohol 13.5%. The oral solution also contains FD&C Red #40, glycerin, sucrose, wild cherry flavor, and purified water. image description