This chapter will provide a brief overview of the psychopharmacology of disorders of sleep and wakefulness. Included here are short discussions of the symptoms, diagnostic criteria, and treatments for disorders that cause insomnia, excessive daytime sleepiness, or both. Clinical descriptions and formal criteria for how to diagnose sleep disorders are mentioned here only in passing. The reader should consult standard reference sources for this material. The discussion here will emphasize the links between various brain circuits and their neurotransmitters with disorders that cause insomnia or sleepiness. The goal of this chapter is to acquaint the reader with ideas about the clinical and biological aspects of sleep and wakefulness, how various disorders can alter sleep and wakefulness, and how many new and evolving treatments can resolve the symptoms of insomnia and sleepiness.

Psychotropic drugs have many mechanisms of action, but they all target specific molecular sites that have profound effects upon neurotransmission. It is thus necessary to understand the anatomical infrastructure and chemical substrates of neurotransmission (Chapter 1) in order to grasp how psychotropic drugs work. Although there are over 100 essential psychotropic drugs utilized in clinical practice today (see Stahl’s Essential Psychopharmacology: the Prescriber’s Guide), there are only a few sites of action for all these therapeutic agents (Figure 2-1). Specifically, about a third of psychotropic drugs target one of the transporters for a neurotransmitter; another third target receptors coupled to G proteins; and perhaps only 10% target enzymes. All three of these sites of action will be discussed in this chapter. The balance of psychotropic drugs target various types of ion channels, which will be discussed in Chapter 3. Thus, mastering how just a few molecular sites regulate neurotransmission allows the psychopharmacologist to understand the theories about the mechanisms of action of virtually all psychopharmacological agents.

Many important psychopharmacological drugs target ion channels. The role of ion channels as important regulators of synaptic neurotransmission have been covered in Chapter 1. Here we discuss how targeting these molecular sites causes alterations in synaptic neurotransmission that are linked in turn to the therapeutic actions of various psychotropic drugs. Specifically, we will cover ligand-gated ion channels and voltage-sensitive ion channels as targets of psychopharmacological drug action.

This chapter will provide a brief overview of the various causes of dementia and their pathologies, including the most recent diagnostic criteria, and how biomarkers are beginning to be integrated into clinical practice, especially for Alzheimer disease (AD). Full clinical and pathological descriptions and formal criteria for how to diagnose the numerous known dementias should be obtained by consulting standard reference sources. The discussion here will emphasize how various pathological mechanisms in different dementias disrupt brain circuits and their neurotransmitters. We will also show how disruption of these brain circuits is linked to various symptoms of dementia, and how drugs targeting these brain circuits and their neurotransmitters lead to symptomatic improvement, emphasizing memory, psychosis, and agitation. The goal of this chapter is to acquaint the reader with ideas about the clinical and biological aspects of dementia and its current management with various approved drugs as well as novel agents on the horizon.

Psychosis is a difficult term to define and is frequently misused not only in the media, but unfortunately among mental health professionals as well. Stigma and fear surround the concept of psychosis, sometimes using the pejorative term “crazy.” This chapter gives a general description of psychotic symptoms and explores the major theories of how all forms of psychosis are linked to the neurotransmitter systems dopamine, serotonin, and glutamate. An overview of specific psychotic disorders, with an emphasis on schizophrenia, is presented here but does not list the diagnostic criteria for all the disorders in which psychosis is either a defining feature or an associated feature. The reader is referred to standard reference sources such as the DSM (Diagnostic and Statistical Manual of the American Psychiatric Association and the ICD (International Classification of Diseases) for that information. Although schizophrenia is emphasized here, we will approach psychosis as a syndrome associated with a variety of disorders that are all targets for the various drugs that treat psychosis and that will be discussed in the following Chapter 5.

In this chapter, we will review pharmacological concepts underlying the use of drugs used to treat mood disorders, from depression, to mixed states, to mania. These agents have classically been called “antidepressants” and “mood stabilizers” but this terminology is now considered out of date and confusing since not all drugs classically called “antidepressants” are used to treat all forms of depression – especially not bipolar depression or depression with mixed features. Furthermore, many of the classic so-called “antidepressants” are also used to treat a whole range of disorders from anxiety disorders, to eating disorders, traumatic disorders, obsessive compulsive and impulsive disorders, pain, and beyond. Finally, many of the drugs used for psychosis and discussed extensively in Chapter 5 are used even more commonly to treat depression, unipolar, bipolar, and mixed depression, as well as mania, yet are not generally classed as “antidepressants” although they are certainly “drugs for depression.” To eliminate confusion about how to discuss categories of drugs, throughout this textbook we strive to utilize modern neuroscience-based nomenclature, where drugs are named for their pharmacological mechanism of action and not for their clinical indication.

Modern psychopharmacology is largely the story of chemical neurotransmission. To understand the actions of drugs on the brain, to grasp the impact of diseases upon the central nervous system, and to interpret the behavioral consequences of psychiatric medicines, one must be fluent in the language and principles of chemical neurotransmission. The importance of this fact cannot be overstated for the student of psychopharmacology. This chapter forms the foundation for the entire book, and the roadmap for one’s journey through one of the most exciting topics in science today, namely the neuroscience of how disorders and drugs act upon the central nervous system.

This chapter will provide a brief overview of chronic pain conditions associated with different psychiatric disorders and treated with psychotropic drugs. Included here are discussions of the symptomatic and pathophysiological overlap between disorders with pain and many other disorders treated in psychopharmacology, especially depression and anxiety. Clinical descriptions and formal criteria for how to diagnose painful conditions are only mentioned here in passing. The reader should consult standard reference sources for this material. The discussion here will emphasize how discoveries about the functioning of various brain circuits and neurotransmitters – especially those acting upon the central processing of pain – have impacted our understanding of the pathophysiology and treatment of many painful conditions that may occur with or without various psychiatric disorders. The goal of this chapter is to acquaint the reader with ideas about the clinical and biological aspects of the symptom of pain, how it can hypothetically be caused by alterations of pain processing within the central nervous system, how it can be associated with many of the symptoms of depression and anxiety, and finally, how it can be treated with several of the same agents that can treat depression and anxiety. The discussion in this chapter is at the conceptual level, and not at the pragmatic level. The reader should consult standard drug handbooks (such as Stahl’s Essential Psychopharmacology: the Prescriber’s Guide) for details of doses, side effects, drug interactions, and other issues relevant to the prescribing of these drugs in clinical practice.

Typical or first-generation antipsychotic (FGA)

Typical or first-generation antipsychotic (FGA)