ABSTRACT

TABLE 47-1. Classification of barbiturates by duration of action

Ultrashort-acting Thiopental Methohexital Buthabital Hexobarbital Thiamylal

Short-and intermediate-acting Amobarbital Aprobarbital Butabarbital Butalbital Pentobarbital Secobarbital Talbutal

Long-acting Phenobarbital Mephobarbital Metharbital

elimination is primarily by metabolic degradation or excre­ tion, and the rate of removal of the active drug from the central nervous system. On the basis of these differences in the duration of action, barbiturates are classified into three categories: ultrashort-acting, short-and intermediate-act­ ing, and long-acting (Table 47-1) (1). The anticonvulsant primidone (Mysoline) is metabolized to phenobarbital and thus should be considered a barbiturate (4).