Hypnotics: Course and Duration of Therapy, Side Effects, Contraindications, Interactions, Withdrawal Syndromes, and Resistance to Therapy

Abstract

Difficulties in falling asleep, maintaining sleep, and early morning awakening characterize insomnia. It is the most widely reported sleep problem, occurring in about 36.8% of the general population in industrialized countries and affecting approximately 50% of people at some point. Although it can be an independent disorder and referred to as primary, it is most frequently observed in comorbidity with several physical and mental illnesses, these being precipitated, exacerbated, or prolonged by insomnia. Chronic insomnia, either primary or as a comorbid disorder, is a prevalent condition associated with reduced productivity, increased risk of accidents, and poor quality of life. Although a detailed history and thorough physical examination can help in its evaluation, treatment can be complex and time-consuming for patients and providers. To date, pharmacologic and behavioral treatments are available, each one presenting advantages and limitations. Psychological/behavioral therapies are regarded as first-line intervention by various specialty societies. Pharmacotherapy can be an adjunctive tool when symptoms persist or if patients cannot undertake cognitive behavioral therapies. The scope of this chapter is to summarize the available pharmacological treatments most commonly prescribed for chronic insomnia in adults. The following groups are discussed: benzodiazepines and non-benzodiazepine gamma aminobutyric acid receptor agonists, the dual orexin receptor antagonist suvorexant, melatonin and its receptor agonists, sedating antidepressants, and a miscellaneous including histamine receptor antagonists. Together with the neurobiological and pharmacologic properties, clinical effects of these drugs are described, including subjective and objective effects on sleep duration, continuity, and architecture.