Clinical distinctions between long-acting and short-acting benzodiazepines.

After their clinical introduction in the 1960s, the benzodiazepines rapidly became the most widely prescribed sedative/hypnotics because of their many advantages over barbiturates and other older agents. Along with this popularity came controversy, which has continued to this day. The most recent form this has taken has been the concern that the short-acting benzodiazepines may have a predisposition to induce certain forms of clinical complications. The author reviews the historical framework in which this controversy arose. In the late 1970s and early 1980s, it became increasingly clear that long-acting agents were associated with daytime sedation as well as cognitive and psychomotor impairment, particularly in the elderly. The short-acting benzodiazepines, which greatly reduced the frequency of these types of effects, rapidly became the most widely prescribed agents. A growing body of data indicates that the short-acting hypnotics are less likely to be associated with falls and hip fractures in the elderly and also have less respiratory depressant qualities, compared with the older long-acting agents. The short-acting compounds may also be more efficacious in inducing sleep during the first night of administration. In contrast, the long-acting agents may be more desirable in those cases in which daytime sedation is desired and may be associated with a delayed and milder withdrawal sleep disturbance. With the short-acting agents, however, sleep disturbance upon drug cessation is dose dependent and may be greatly reduced by tapering the dose.