Benzodiazepine sedative-hypnotics clinical pharmacology

Some sedative-hypnotics, particularly members of the carbamate (eg, meprobamate) and benzodiazepine groups, exert inhibitory effects on polysynaptic reflexes and internuncial transmission and at high doses may also depress transmission at the skeletal neuromuscular junction. Somewhat selective actions of this type that lead to muscle relaxation can be readily demonstrated in animals and have led to claims of usefulness for relaxing contracted voluntary muscle in muscle spasm (see Clinical Pharmacology). Muscle relaxation is not a characteristic action of zolpidem, zaleplon, and eszopiclone. 

Introduction - Although an effort has been made in this chapter to exclude depressants classified in other chapters as antipsychotic and antianxiety agents, certain benzodiazepines will be considered here because of the number of compounds in this series which have been found clinically to possess sedative-hypnotic and anticonvulsant activity. In most cases, compounds with more than preliminary pharmacological data or representatives of new structural types were selected for inclusion in this chapter. 

In this chapter, we discuss the pharmacology of medications that are classified as anxiolytic, sedative, or hypnotic—primarily the benzodiazepines, buspirone, zolpidem, eszopiclone, and zale-plon. Subsequently, we present diagnosis-specific treatment guidelines (outlined in Table 3-1). The commonly used anxiolytics and hypnotics, together with their usual doses, are shown in Table 3-2. Many antidepressant medications are also effective in the treatment of anxiety disorders. The pharmacology of antidepressants is discussed in Chapter 2 their clinical use in anxiety disorders is addressed in the diagnosis-specific sections later in this chapter. 

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