Drug therapy: The diagnosis and management of insomnia

A guide to benzodiazepine selection. Part II: Clinical aspects

To suit the specific needs of various clinical situations, selection of an appropriate benzodiazepine derivative should be based on consideration of their different pharmacokinetic and pharmacodynamic properties. Benzodiazepine derivatives that are rapidly eliminated produce the most pronounced rebound and withdrawal syndromes. Benzodiazepines that are slowly absorbed and slowly eliminated are most appropriate for the anxious patient, since these derivatives produce a gradual and sustained anxiolytic effect. Rapidly absorbed and slowly eliminated benzodiazepines are usually more appropriate for patients with sleep disturbances, since the rapid absorption induces sleep and the slower elimination rate may induce less tolerance to the sedative effect. Rational selection of a benzodiazepine for the elderly and for the suspected drug abuser is more problematic. The relevant pharmacokinetic and clinical considerations for these users are discussed. Certain derivatives may possess pharmacodynamic properties not shared by the entire benzodiazepine class; empirical studies have suggested the existence of anti-panic properties for alprazolam and clonazepam, antidepressant properties for alprazolam, and anti-manic properties for clonazepam and possibly lorazepam.

Benzodiazepines and the elderly. A review of potential problems

This article reviews the literature describing the extent of benzodiazepine use and abuse in the elderly and specific problems attendant upon this use, Unrecognized, undocumented use and abuse of psychoactive drugs is frequent in this population and can lead to serious problems with untreated dependence and withdrawal. The elderly appear to be more sensitive to the effects of benzodiazepines, both because of changed pharmacokinetics and pharmacodynamics with aging and because of altered postreceptor cerebral response. All problems identified with benzodiazepines such as dependence, withdrawal, and cognitive and psychomotor impairment are proportionally greater among the elderly, who can least afford these risks. Review of the literature leads to the conclusion that benzodiazepine prescribing for the elderly should be undertaken with the greatest caution and only with the recognition of all potentially disastrous effects.