Chapter 233. Sedatives

1. How common are alcohol and sedative dependence in the general hospital setting?

2. How is alcohol withdrawal optimally managed?

3. What factors make it more likely for a patient to develop delirium tremens?

4. What are the differences in management of withdrawal from alcohol, benzodiazepines, and barbiturates?

5. What should be done with the patient dependent on alcohol or a sedative following the inpatient medical hospitalization?

Sedatives constitute a diverse group of agents, including alcohol (ethanol, ethyl alcohol, EtOH), benzodiazepines, nonbenzodiazepine hypnotic medications (so-called Z-drugs such as zolpidem [Ambien]), barbiturates, and several other compounds, including chloral hydrate and meprobamate. The class also includes gamma hydroxybutyrate (GHB), a short-acting sedative, which is specifically addressed in Chapter 236, “Other Drugs of Abuse.” The agents covered in this chapter collectively are often referred to as sedatives, sedative-hypnotics, or sometimes hypnotics. Here the term sedatives will be used for this class of compounds; it will not apply to all classes of medications (eg, antihistamines, various antidepressants, antipsychotics, opioids, and others) that may produce sedation. Note that while the Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR) uses the term sedative-hypnotic, this chapter employs the term sedative for the same class of agents. While all sedatives may produce drowsiness, sleep, and a feeling of relaxation, they do not always do so, particularly when tolerance has developed. Many sedatives also produce muscle relaxation, and all may produce addiction (see Diagnosis section for definition), which will likely complicate and exacerbate the course of the underlying disorder(s) that led to hospitalization.

The sections in this chapter specifically cover alcohol, benzodiazepines, Z-drugs (zolpidem, zaleplon, zopiclone, eszopiclone), barbiturates, and others, as appropriate. All sedatives, including alcohol, have the common effect of dose-dependently depressing neuronal function, though this may occur by one or more mechanisms. Most of these agents, in overdose, may produce fatal respiratory depression, but this is rarely the primary reason for use. Human beings have used alcohol for countless millennia to produce many desired effects, including diminished anxiety, relaxation, sleep, analgesia, and intoxication. Sedating medicinal plants have also been employed for millennia, usually to facilitate sleep and less often for any of many other purposes, some of which reflect the actual pharmacology of one or more compounds present in the plant(s). It is beyond the scope of this chapter, however, to address sedating herbs and other medicinal plants.

Epidemiology of Alcohol Use Disorders

Estimates of the prevalence of alcohol use disorders in the general population vary, in part depending on the country being surveyed and the diagnostic criteria used, but a recent estimate put the lifetime prevalence of alcohol dependence (according to DSM-IV-TR) at 12.5% in the United States. Estimates of the prevalence of alcohol dependence among hospitalized patients also vary, partly because studies have employed different methods to ascertain and define alcohol use disorders, and because some studies have included measures of “at risk” drinking rather than alcohol use ...