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Varcarolis’s Canadian Psychiatric Mental Health Nursing Chapter 03: Relevant Theories and Therapies for Nursing Practice Instructor’s Manual Thoughts About Teaching the Topic When students have completed a growth and development course prior to the psychiatric nursing course, a review of personality theories by reading may be sufficient. It’s wise, however, to offer a self-paced activity or a match exercise and remind students that they are responsible for the content, whether or not it is included in a lecture. The chapter’s explanation of therapies is succinct, yet it is sufficient in detail to permit learners to grasp the material. However, because learners have a limited frame of reference for therapies, most would rather explore what those in the field think rather than discuss or debate among themselves. Use of a film, followed by a discussion, may help learners grasp the basic principles and concepts of therapy. Key Terms and Concepts automatic thoughts behavioural therapy biofeedback classical conditioning cognitive-behavioural therapy (CBT) cognitive distortions conditioning conscious counter-transference defence mechanisms ego extinction id interpersonal psychotherapy milieu therapy negative reinforcement operant conditioning positive reinforcement preconscious psychodynamic therapy punishment reinforcement superego transference unconscious Objectives Evaluate the premises behind the various therapeutic models discussed in this chapter. Describe the evolution of therapies for psychiatric disorders. Identify ways each theorist has contributed to the nurse’s ability to assess a patient’s behaviours. Drawing on clinical experience, provide the following: An example of how a patient’s irrational beliefs influenced behaviour An example of counter-transference in your relationship with a patient An example of the use of behaviour modification with a patient Identify Peplau’s framework for the nurse–patient relationship. Choose the therapeutic model that would be most useful for a particular patient or patient problem. Chapter Outline Teaching Strategies Major Theories of Personality The contributions of Freud, Erikson, Sullivan, Peplau, and Maslow are summarized. Sigmund Freud’s Psychoanalytic Theory 1. Through the use of talk therapy and free association, Freud came to believe that there were three levels of psychological awareness. He used the image of an iceberg to describe these levels of awareness. Conscious—the part of the mind he compared to the tip of the iceberg. It contains all the material a person is aware of at any one time, including perceptions, memories, thoughts, fantasies, and feelings. Preconscious—just below the surface of awareness which contains material that can be retrieved rather easily through conscious effort. Unconscious—this includes all repressed memories, passions, and unacceptable urges lying deep below the surface. Emotions associated with trauma are often “placed” in the unconscious because the individual finds it too painful to deal with them. It is usually too difficult to retrieve unconscious material without the assistance of a trained therapist. Personality structure is described as three categories of experience: Id—source of drives and instincts; includes genetic inheritance; reflexes, wishes that motivate us; uses pleasure principle, is not logical, and lacks the ability to problem solve. Ego—develops because the needs, wishes, and demands of the id cannot be satisfactorily met through primary processes and reflex action. The ego emerges in the fourth or fifth month of life and follows the reality principle, which says to the id, “You have to delay gratification for 2. right now” and sets a course of action. 3. Superego—internal representative of values, ideals, and moral standards of society; strives for perfection as opposed to seeking pleasure or engaging reason. The superego consists of the conscience (all the “should nots” internalized from parents) and the ego ideal (all the “shoulds” internalized from parents). In a mature and well-adjusted individual, the three systems of the personality work together as a team under the leadership of the ego. Freud suggested that ego defence mechanisms are developed to reduce anxiety by denying, falsifying, or distorting reality to prevent conscious awareness of threatening feelings. These mechanisms operate unconsciously. He further wrote that the individual proceeds through a series of psychosexual stages of development from infancy to adulthood. Each stage (except latency) refers to the bodily zone that produces the main source of gratification during the stage. Each stage has its own conflict to be resolved: 1. Oral—0 to 1 year: weaning Anal—1 to 3 years: toilet training Phallic—3 to 6 years: oedipal conflict Latency—6 to 12 years: hides sexuality from disapproving adults Genital—12 to 20 years: genital sexuality Classical Psychoanalysis Classical psychoanalysis, among the least practised therapies and the most expensive, calls for protracted one-on-one therapy with an analyst. It makes use of free association and working through transference to uncover unconscious feelings and thoughts that interfere with the patient’s life. The patient is more active than the therapist. Psychodynamic Therapy The psychodynamic approach to therapy “understands that unconscious dynamics exist within normal human consciousness and that it is possible in therapy to engage many aspects of the human psyche in ways that are useful, creative, and healing” (Canadian Association for Psychodynamic Therapy, n.d., para. 2). The best candidates for brief psychotherapy are relatively healthy and well-functioning individuals, sometimes referred to as the “worried well,” who have a clearly circumscribed area of difficulty and are intelligent, psychologically minded, and well motivated for change. Patients with psychosis, severe depression, borderline personality disorders, and severe character disorders often are not appropriate candidates for this type of treatment. Supportive therapies, which are within the scope of practice of the basic-level psychiatric nurse, are useful for these patients. A variety of supportive therapies are described in chapters concerning specific disorders (see Chapters 13 to 23). There is a general understanding that psychotherapy does not cure but that it can help troubled individuals learn to recognize that problems exist and can promote self-awareness as they deal with life’s inevitable stressors. Erik Erikson’s Ego Theory To Erikson, personality is not set in stone at age 5, as Freud suggested, but continues to develop throughout the lifespan. Erikson described development as occurring in eight predetermined and consecutive life stages, each of which consists of two possible outcomes (e.g., industry versus inferiority from ages 7 to 12). Harry Stack Sullivan’s Interpersonal Theory Sullivan’s interpersonal theory focused on interpersonal processes observed in a social framework. Major aspects of his theory deal with anxiety and self-system. Anxiety can be transmitted interpersonally via empathetic linkage and can be described. Behaviours resulting from anxiety can be observed, and security operations such as selective inattention and dissociation are measures used to reduce it. Interpersonal Psychotherapy This therapy focuses on reassurance, clarification of feeling states, and improvement in interpersonal communication and interpersonal skills. The therapist identifies the nature of the problem and selects strategies for use. Four types of problem areas have been identified: grief, role disputes, role transition, and interpersonal deficit. Hildegard Peplau’s Theory of Interpersonal Relationships in Nursing Peplau, influenced by Sullivan’s interpersonal theory, developed the first systematic theoretical framework for psychiatric nursing, the one-to-one nurse–patient relationship. Her theory is mainly concerned with the processes by which the nurse helps patients make positive changes in their health care status and well-being. Peplau identified stages of the nurse–patient relationship and used process recording to assist her students to hone their communication relationship skills. She describes skills the psychiatric nurse will use, including observation, interpretation, and intervention. Peplau also believed that nurses working with psychiatric patients need to have an awareness of their own behaviour. She believed this self-awareness for the nurse is essential in order to keep the focus on the patient. Peplau spent a lifetime illuminating the science and art of professional nursing practice, which has had a profound effect on the nursing profession, nursing science, and the clinical practice of psychiatric nursing. Behavioural Theories and Therapies Behavioural therapies developed as a protest response to Freud’s assumption that a person’s destiny was carved in stone at a very early age. Behaviourists have no concern with inner conflicts but argue that personality simply consists of learned behaviours. Behavioural models emphasize the ways in which observable behavioural responses are learned and can be modified in a particular environment. Ivan Pavlov’s Classical Conditioning Theory Ivan Pavlov formalized his observations of dogs in a theory of classical conditioning. An example of this in humans would be when an individual becomes very ill after eating spoiled coleslaw and later in life feels nauseated whenever he smells coleslaw. It is important to recognize that classical conditioned responses are involuntary, not under conscious control, and are not spontaneous choices. John B. Watson’s Behaviourism Theory Used to treat relatively healthy patients who have a circumscribed area of difficulty and who are willing to change. Usually 10 to 25 sessions are involved. Both patient and therapist actively participate. Assessment is rapid and early. Goals are concrete and focused on lessening the patient’s worst symptoms, helping the patient understand what is going on in his or her life, and enabling him or her to cope better. Interpretations are directed toward present life circumstances. Some positive transference is fostered to encourage the patient to follow the therapist’s suggestions. B.F. Skinner’s Operant Conditioning Theory B.F. Skinner represented the second wave of behavioural theorists. Skinner (1987) researched operant conditioning, in which voluntary behaviours are learned through consequences, and behavioural responses are elicited through reinforcement, which causes a behaviour to occur more frequently. Behavioural Therapy Based on learning theory. Maladaptive behaviour can be unlearned and adaptive behaviour learned. Useful techniques include modelling, operant conditioning, systematic desensitization, and aversion. Modelling In modelling, the therapist provides a role model for specific identified behaviours, and the patient learns through imitation. Operant Conditioning Operant conditioning is the basis for behaviour modification and uses positive reinforcement to increase desired behaviours. Systemic Desensitization 1. Systematic desensitization is another form of behaviour modification therapy that involves the development of behavioural tasks customized to the patients’ specific fears; these tasks are presented to the patient while he or she is using learned relaxation techniques. The process involves four steps: The patient’s fear is broken down into its components by exploring the particular stimulus cues the patient presents. The patient is incrementally exposed to the fear. Patients are instructed how to design their own hierarchies of fear. Patients practice these techniques every day. Aversion Therapy Aversion therapy, which is akin to punishment, is used widely to treat such behaviours as alcoholism, sexual deviation, shoplifting, and others. Three paradigms for using aversive techniques are: 1. Pairing of a maladaptive behaviour with a noxious stimulus so anxiety or fear becomes associated with the oncepleasurable stimulus Punishment Avoidance training Biofeedback Biofeedback is a form of behavioural therapy that uses sensitive instrumentation to acquire information about bodily functions such as muscle activity, brain waves, skin temperature, heart rate, and blood pressure. Biofeedback is successfully used today, especially for controlling the body’s physiological response to stress and anxiety. Cognitive Theories and Therapies Cognitive theories and therapies are active, directive, and timelimited. Cognitive therapy is based on the rationale that individual affect and behaviour are determined by the way in which the individual’s cognitions structure the world. The therapist helps identify, reality-test, and correct distorted conceptualizations and dysfunctional beliefs. The patient learns to think more realistically and adaptively, thus reducing symptoms. A number of therapies incorporate these approaches, rational-emotive behaviour therapy (REBT), and cognitivebehavioural therapy (CBT) among them. Humanistic Theories Humanistic theories focus on human potential and free will to choose life patterns that are supportive of personal growth. Abraham Maslow’s Humanistic Psychology Theory Maslow’s hierarchy of six incremental stages assumes that humans are active rather than passive participants in life, striving for self-actualization. Biological Theories and Therapies The biological model of mental illness focuses on neurological, chemical, biological, and genetic issues and seeks to understand how the body and brain interact to create emotions, memories, and perceptual experiences. The recognition that psychiatric illnesses are as physical in origin as diabetes and coronary heart disease serves to decrease the stigma surrounding psychiatric illnesses. Milieu Therapy This therapy establishes a safe, supportive environment with an emphasis on group and social interaction. Rules are mediated by peer pressure, the staff view the patients as responsible humans, patients are involved in goal setting, patients have freedom of movement, and there are informal patient–staff relationships and interdisciplinary staff participation. Additional Therapies Other therapeutic approaches will be introduced later in the book. Crisis intervention, group therapy, and family therapy are examples. Varcarolis’s Canadian Psychiatric Mental Health Nursing Chapter 04: Psychotropic Drugs Instructor’s Manual Thoughts About Teaching the Topic Some of the material presented in this chapter reviews material learned in previous anatomy and physiology courses. The authors use this basic material to promote understanding of the possible disturbances associated with each of the groups of major mental disorders and go on to look at the fact that pharmacological treatment is directed at suspected transmitter– receptor problems. Side effects and adverse effects are often related to blockade of various neurotransmitters. A major task of the instructor is to help the student appreciate the results of an increase and decrease of each transmitter and to simplify understanding of psychotropic drug action and adverse effects. Instruction should focus on understanding these broad neurochemical actions that relate to groupings of drugs—refraining from memorizing a list for each drug. Learning activities that help the learner associate drug name, action classification, and adverse effects can be very helpful. Key Terms and Concepts agonist antagonist antianxiety (anxiolytic) drugs anticholinesterase drugs atypical antipsychotics biopsychiatry circadian rhythms conventional antipsychotics hypnotic limbic system lithium carbonate metabolites monoamine oxidase inhibitors (MAOIs) mood stabilizer neurons neurotransmitters pharmacodynamics pharmacogenetics pharmacokinetics receptors reticular activating system (RAS) reuptake selective serotonin reuptake inhibitors (SSRIs) synapse therapeutic index tricyclic antidepressants (TCAs) Objectives Identify the functions of the brain and discuss how these functions can be altered by psychotropic drugs. Describe how a neurotransmitter functions as a neuromessenger. Identify the functions of the three major areas of the brain. Explain how specific brain functions are altered in mental health disorders such as depression, anxiety, bipolar disorder, and schizophrenia. Describe how imaging techniques are used to map brain structure and function in individuals with mental health disorders. Describe the result of blockage of the muscarinic receptors and the α1 adrenergic receptors by the standard neuroleptic drugs. Identify the main neurotransmitters affected by the following psychotropic drugs and their subgroups: Antianxiety drugs Sedative–hypnotic drugs Antidepressants Mood stabilizers Antipsychotic drugs Anticholinesterase drugs Discuss dietary and drug restrictions for a patient taking a monoamine oxidase inhibitor. 9. Identify specific cautions for a patient taking natural health products and psychotropic drugs. 10. Explore the relevance of pharmacogenetics (i.e., variations in effects and therapeutic actions of medications among different ethnic groups) in the use of psychotrophic drugs. Chapter Outline Teaching Strategies Introduction Biopsychiatry, sometimes referred to as the biological approach, is a theoretical approach to understanding mental health disorders as biological malfunctions of the nervous system. Implied in this approach is the idea that brain function is related to several factors, including genetics, neurodevelopmental factors, drugs, infection, psychosocial experience, or a combination of more than one of these factors that impact brain functioning. Clinicians using this approach believe that changes in the patient’s behaviour and in mental and emotional experiences are caused by damage to the brain. For example, when the brain is damaged, the way it produces and responds to neurotransmitters—the “chemical messengers” of the nervous system—changes. These changes can result in depressive symptoms, symptoms of anxiety, symptoms of post-traumatic stress disorder, or any other combination of behavioural, emotional, or mental symptoms. Medication is used to augment the effectiveness of the neurotransmitters. The primary goal of drug therapy is to restore “balance” to a malfunctioning brain. During recent years, there has been an explosion of information about the efficacy of psychotropic drugs (medication to treat mental illness) in reversing these alterations; however, a full understanding of how these drugs improve symptoms continues to elude investigators. Functions and Activities of the Brain Brain functions include monitoring changes in the external world; monitoring the composition of body fluids; regulating contractions of skeletal muscles; regulating internal organs; initiating and regulating basic drives (hunger, thirst, sex, aggressive selfprotection); conscious sensation; memory; thought; mood (affect); language; and regulating the sleep cycle. The following are ways in which psychiatric illness and its treatments alter each of these functions: Function Alteration Monitoring external world Altered sensory experiences (hallucinations, illusions) Control over skeletal muscles Movement disturbances (extrapyramidal side effects [EPS]), respiratory alterations, slurred speech Regulating internal organs Blood pressure variations dependent upon autonomic nervous system; anxiety activates parasympathetic nerves; hormonal effects such as menstrual cycle disturbances; corticotropinreleasing hormone (CRH) effect on general response to stress Regulating basic drives Over- or undereating, loss of sexual drive Regulating sleep cycle Sleep disturbance as a symptom of psychological distress, hypervigilance, drowsiness Mood Affected by circadian variations and neurotransmitter secretion (especially serotonin and norepinephrine) Conscious experience Inability to focus stream of consciousness or interpret external world, distorted thought patterns (loose associations), distorted speech (word salad), delusions Memory Inability to retain or recall past experience; cognitive disorders; learning disorders Cellular Composition of the Brain Neurons are specialized cells in the central nervous system (CNS), each having a cell body, an axon, and dendrites. Each neuron carries out three types of physiological actions: they respond to stimuli, conduct electrical impulses, and release neurotransmitters. Conduction of electrical impulses involves self-propagating changes in membrane permeability, allowing inward flow of sodium ions followed by outward flow of potassium ions, changing polarity, and creating an electrical charge along the length of the membrane. When the impulse reaches the end of the neuron, a neurotransmitter is released from the axon terminal. The neurotransmitter spreads across the synapse and attaches to a receptor on the surface of the next neuron. Then it detaches and is either destroyed or taken back into the cell from which it was originally released (reuptake), where it may be reused or destroyed. Organization of the Brain The explanation of a neuron releasing a specific transmitter that stimulates or inhibits a postsynaptic membrane receptor and acts via negative feedback on a presynaptic receptor is accurate but incomplete. Neurons release more than one chemical at a time (e.g., neuropeptides that may initiate long-term changes in the postsynaptic cells is a topic of investigation). Neuron development and responsiveness are also affected by chemicals brought by the blood (e.g., steroid hormones, as evidenced by psychosis resulting from hypersecretion of cortisol in Cushing’s disease and use of prednisone to treat chronic inflammatory disease). Brain Stem The brainstem regulates internal organs, is responsible for vital functions, and is the initial processing centre for sensory information that is sent to the cerebral cortex. The reticular activating system (RAS) of the brain stem regulates sleep and wakefulness and, by reaching into the limbic system of the cerebrum, it affects the ability of the cerebrum to carry out conscious mental activity. The mesolimbic and mesocortical pathways project into the limbic system and seem to have a role in modulating the emotional value of sensory material. Cerebellum The cerebellum regulates skeletal muscle coordination and the maintenance of equilibrium. Cerebrum The cerebrum is responsible for mental activities, conscious perception, emotional states, memory, control of skeletal muscles for wilful movement, language, and communication. The cerebral cortex is responsible for conscious sensation and initiation of movement. Basal ganglia, areas of integrating grey matter within the cerebrum, are involved in movement regulation, and the amygdala and hippocampus are involved in the emotions, learning, memory, and basic drives. As a consequence, drugs used to treat emotional disturbances may cause movement disorders, and drugs used to treat movement disorders may cause emotional changes. Imaging techniques are used to visualize brain structure. Structural techniques—computed tomography (CT) and magnetic resonance imaging (MRI)—scans can identify gross anatomical changes in the brain. Functional imaging techniques—positron emission tomography (PET) and single-photon emission computed tomography (SPECT) scans—identify physiological and biochemical changes in live tissue. Functional scans suggest the frontal cortex as the site of impairment in people with schizophrenia and people with obsessive-compulsive disorder (OCD), and the prefrontal cortex as the site of impairment in individuals with depression. It is presently thought that the limbic system (with its group of structures that includes parts of the frontal cortex, the basal ganglia, and brain stem) is a major locus of psychological activity. Within these areas, monoamine transmitters (norepinephrine, dopamine, serotonin), acetylcholine, -aminobutyric acid (GABA), glutamate, CRH, and endorphin are found and may provide targets for pharmacological treatment. Disturbances of Mental Function Some mental disturbances are related to certain drugs (e.g., LSD), excess levels of hormones (e.g., cortisol), infection (e.g., AIDS), or physical trauma (e.g., strokes). Others are of unknown etiology but may well be related to genetic factors. The incidence of both thought and mood disorders is higher in relatives of people with these diseases than in the general population. Neurotransmitters that have most consistently been linked to mental activity are norepinephrine, dopamine, serotonin, GABA, glutamate, and CRH. Often a particular transmitter is used by different neurons to carry out quite different functions; thus, alterations in transmitter activity can affect more than one area of brain activity. Alterations in mental status, whether arising from disease or medication, are often accompanied by changes in basic drives, sleep patterns, body movement, and autonomic functions. Mechanisms of Action of Psychotropic Drugs Important concepts: pharmacodynamics—refers to the actions of the drug on the person (large-scale and molecular); pharmacokinetics—refers to the actions of the person on the drug (absorption, excretion, etc.). An ideal psychotropic drug would relieve mental disturbance without inducing untoward mental or physical effects. Most psychotropic drugs act by either increasing or decreasing the activity of certain transmitter–receptor systems. Specific transmitter-receptor systems are targets for drug action. Antianxiety and Hypnotic Drugs GABA exerts an inhibitory effect on neurons in many parts of the brain. Drugs that enhance this effect exert a sedative–hypnotic action on brain function and reduce anxiety. Benzodiazepines Diazepam (Valium), clonazepam (Rivotril), and alprazolam (Xanax) bind to specific receptors adjacent to GABA receptors. Benzodiazepine binding at sites adjacent to GABA binding allows GABA to inhibit more forcefully than it would if binding alone. Benzodiazepine potentiation of GABA accounts for its use as an anticonvulsant and its efficacy in reducing neuronal overexcitement in alcohol withdrawal. These drugs can also interfere with motor ability, attention, and judgement. Short-Acting Sedative–Hypnotic Sleep Drugs Zopiclone (Imovane) is a newer class of hypnotic, termed a Zdrug. Structurally, it is unrelated to existing hypnotics; however, zopiclone also promotes GABA and inhibits the release of neurotransmitters. As a result, it has sedative effects as well as hypnotic, anxiolytic, anticonvulsant, and muscle-relaxant effects. The onset of action is faster than that of most benzodiazepines. It is important to inform patients taking nonbenzodiazepine hypnotic drugs about the quick onset and advise them to take the drug only when they are ready to go to sleep. Buspirone Buspirone (Bustab) reduces anxiety without strong sedative– hypnotic effects. Its action is unclear, but it may block presynaptic 5-HT1 receptors, preventing negative feedback and allowing more transmitter to be released. Antidepressant Treatment for Conditions Associated With Anxiety Many antidepressants have proven to be effective treatments for anxiety disorders (Stahl, 2008). Selective serotonin reuptake inhibitors (SSRIs), medications that increase both serotonin and norepinephrine, are often used to treat obsessive-compulsive disorder (OCD), social anxiety disorder (SAD), generalized anxiety disorder (GAD), panic disorder (PD), and post-traumatic stress disorder (PTSD). Venlafaxine hydrochloride (Effexor XR) is used to treat GAD, SAD, and PD. Duloxetine hydrochloride (Cymbalta) is approved for major depressive disorder (MDD), for GAD, and for neuropathic pain associated with peripheral neuropathy of diabetes, pain associated with fibromyalgia, and chronic low back pain. Antidepressant Drugs Evidence points to the cause of depression as a transmission deficiency of norepinephrine or serotonin or both within the limbic system. Tricyclic Antidepressants Amitriptyline (Elavil), imipramine (Impril), and nortriptyline (Aventyl)—tricyclic antidepressants (TCAs)—act primarily by blocking reuptake of norepinephrine and, to a lesser degree, serotonin; thus norepinephrine is not degraded by monoamine oxidase (MAO), and more stays at the synapse. TCAs block muscarinic receptors, giving anticholinergic effects. Some TCAs block H1 receptors in the brain, producing drowsiness. Selective Serotonin Reuptake Inhibitors Fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), escitalopram (Cipralex), fluvoxamine (Luvox), and citalopram (Celexa) block the reuptake of serotonin with little or no effect on the other monoamine transmitters. These drugs have less ability to block muscarinic and H1 receptors than do the tricyclics (TCAs). Serotonin– Norepinephrine Reuptake Inhibitors (SNRIs) Serotonin–norepinephrine reuptake inhibitors (SNRIs) are medications that increase both serotonin and norepinephrine. Venlafaxine hydrochloride (Effexor XR) and its metabolite desvenlafaxine succinate (Pristiq) are potent inhibitors of neuronal serotonin and norepinephrine reuptake and weak inhibitors of dopamine reuptake. This SNRI has the flexibility of working as an SSRI at lower doses (75 mg/day), affecting the reuptake of serotonin, and as an SNRI at higher doses (150–225 mg/day). At doses above 350 mg/day, it also weakly blocks dopamine reuptake. Hypertension, induced in about 5% of patients, is a dosedependent effect based on norepinephrine reuptake blockade. Serotonin and Norepinephrine Disinhibitors The class of drugs described as serotonin and norepinephrine disinhibitors (SNDIs) is represented by only one drug, mirtazapine (Remeron). This unique drug increases norepinephrine, dopamine, and serotonin (5-HT) transmission by blocking central presynaptic α2 adrenergic inhibitory receptors. It may be that mirtazapine, because of its mixed neurotransmitter receptor effects, has a more rapid onset of effect than do single neurotransmitter antidepressant drugs. Mirtazapine is a potent antagonist of 5-HT2 and 5-HT3 receptors, which may account for its antianxiety and antidepressant effects. This antidepressant is also a potent histamine (H1) receptor antagonist, which accounts for drowsiness and increased appetite, resulting in weight gain being the most common adverse effects. Patients may also experience orthostatic hypotension and the occasional occurrence of anticholinergic adverse effects. Monoamine Oxidase Inhibitors Monoamine neurotransmitters, as well as any monoamine food substance or drug, are degraded by the enzyme MAO. Drugs such as phenelzine (Nardil), and tranylcypromine (Parnate) act by inhibiting the enzyme MAO, interfering with the destruction of monoamine neurotransmitters and increasing the synaptic level of the transmitters. In the presence of MAO inhibitors (MAOIs), tyramine is not destroyed in the liver, resulting in hypertensive crisis. Thus, when MAOIs are taken, the patient must observe a tyramine-free diet. Other Antidepressants Bupropion hydrochloride is effective both as an antidepressant (Wellbutrin) and for smoking cessation (Zyban). It seems to act as a dopamine–norepinephrine reuptake inhibitor and also inhibits nicotinic acetylcholine receptors to reduce the addictive action of nicotine. Since bupropion hydrochloride has no serotonin action, it does not cause sexual adverse effects. Adverse effects include insomnia, tremor, anorexia, and weight loss. Mood Stabilizers Lithium The mechanism of action of lithium is unknown but is probably related to affecting electrical conductivity in neurons. It may interact with sodium and potassium at the cell membrane to stabilize electrical activity. Such a mechanism of action would explain its ability to induce cardiac dysrhythmias, convulsions, and tremor. Lithium can also create fluid balance disturbances. For these reasons, it has a low therapeutic index (ratio of lethal dose to effective dose) and requires close monitoring of serum lithium level. Anticonvulsant Drugs These alter electrical conductivity in membranes and reduce the firing rate of very-high-frequency neurons in the brain. This action may account for their use in reducing mood swings in bipolar patients. Valproate (available as sodium divalproex and valproic acid [Depakene]), carbamazepine (Tegretol), and lamotrigine (Lamictal) have demonstrated efficacy in the treatment of bipolar disorders. Valproate Valproate (Depakote, Depakene) is an anticonvulsant. It is structurally different from other anticonvulsants and psychiatric drugs. It is effective in treating manic depression. Common adverse effects include hair loss, tremor, weight gain, and sedation. A baseline of liver function tests and CBC are done before an individual is started on this medication and periodically thereafter. Monitoring of the therapeutic blood level is done regularly as well. Carbamazepine Carbamazepine (Tegretol) is structurally similar to the tricyclic antidepressants. It treats unipolar depression. It is particularly effective in conditions such as trigeminal neuralgia. The efficacy of the drug as an analgesic may be related to its ability to reduce the firing rate of overexcited neurons and its ability to calm the accompanying psychological agitation associated with the pain. Some common adverse effects include nausea, sedation, and ataxia. The therapeutic blood level is monitored regularly. Lamotrigine Lamotrigine (Lamictal) works effectively providing maintenance therapy of bipolar disorder, but it is not effective in acute mania (Preston, 2005). It works well treating the depressive aspect of bipolar disorder. Other Anticonvulsants Other anticonvulsants used as mood stabilizers are gabapentin (Neurontin), topiramate (Topamax), and oxcarbazepine (Trileptal). None of them have Health Canada approval as mood stabilizers, and studies have not provided strong support for their use as primary treatments for bipolar disorders. However, they are used for their calming effects during mania. Chapter 15 offers a more detailed discussion of these medications. Antipsychotic Drugs Conventional Antipsychotics These include the phenothiazines, thioxanthenes, butyrophenones, and so on. These drugs are strong antagonists of the D2 receptors for dopamine. Blocking dopamine reduces the positive symptoms of schizophrenia, such as delusions and hallucinations. These drugs also act as antagonists at muscarinic receptors for acetylcholine, 1 receptors for norepinephrine, and H1 receptors for histamine. Major adverse effects of these drugs arise from receptor-blocking activity: dopamine blockade gives rise to motor disturbances, including parkinsonism, akinesia, akathisia, dyskinesia, and tardive dyskinesia. Involuntary motor movement can be monitored via the abnormal involuntary movement scale (AIMS). Muscarinic receptor blockage leads to anticholinergic effects such as blurred vision, dry mouth, constipation, and urinary hesitancy. Blockade of 1 receptors for norepinephrine is responsible for vasodilation and a consequent orthostatic hypotension and for ejaculatory failure as well. Blockade of H1 receptors contributes to sedation and substantial weight gain. Atypical Antipsychotics Atypical antipsychotics cause few to no EPS. They also target the negative symptoms of schizophrenia as well as the positive symptoms. The difference in motor disturbances results from their preferential binding of dopamine receptors in the limbic system over those in the basal ganglia. They are also antagonists at the 5hydroxytryptamine 2 (5-HT2) receptors for serotonin, which may explain their efficacy in treating the negative symptoms of schizophrenia. Clozapine May induce agranulocytosis, so frequent white blood cell (WBC) counts are required. It may also induce convulsions in a small percentage of patients. Common adverse effects are drowsiness, hypersalivation, tachycardia, and dizziness. Danger of agranulocytosis removes it from first-line usage. Risperidone Reduces delusions and hallucinations. Blocks 1 and H1 receptors and can cause orthostatic hypotension and sedation. Quetiapine Broad receptor binding profile produces sedation and weight gain, along with symptoms associated with muscarinic and 1 blockade. EPS are few. Other Atypical Antipsychotics Olanzapine Olanzapine (Zyprexa) is similar to clozapine in chemical structure. Adverse effects include sedation, weight gain, hyperglycemia with new-onset type 2 diabetes, and higher risk for metabolic syndrome. Ziprasidone Ziprasidone hydrochloride monohydrate (Zeldox) is a serotonin– norepinephrine reuptake inhibitor. The main adverse effects are dizziness and moderate sedation. Ziprasidone is contraindicated in patients with a known history of QT interval prolongation, recent acute myocardial infarction, or uncompensated heart failure. Aripiprazole Aripiprazole (Abilify) is a unique atypical antipsychotic known as a dopamine system stabilizer. In areas of the brain with excess dopamine, it lowers the dopamine level by acting as a receptor antagonist; however, in regions with low dopamine, it stimulates receptors to raise the dopamine level. It induces little sedation or weight gain. Adverse effects include insomnia and akathisia. Paliperidone Paliperidone (Invega) is the major active metabolite of risperidone. It has similar adverse effects to risperidone, such as EPS and prolactin elevation. Additional adverse effects are orthostasis and sedation. It is also available as paliperidone palmitate (Invega Sustenna), a prolonged-release injectable suspension. Drug Treatment of Attention Deficit– Hyperactivity Disorder Psychostimulant drugs such as methylphenidate (Biphentin, Concerta, Ritalin) and dextroamphetamines such as amphetamine aspartate monohydrate (Adderall XR) show efficacy in these conditions. Drug Treatment for Alzheimer’s Disease Much of the memory loss of Alzheimer’s disease has been attributed to dysfunction of neurons that secrete acetylcholine. The anticholinesterase drugs such as donepezil (Aricept) work by inactivating the enzyme that destroys acetylcholine. Natural Health Today, many individuals believe that natural health products Products (NHPs) such as herbal medications or supplements are safer and have fewer adverse effects because they are “natural.” NHPs are thought to be less costly than traditional medicines. During an intake assessment and ongoing interviews with patients, the nurse should include a nonjudgemental set of questions about the patient’s use of NHPs in order to have a holistic view of the patient’s health and treatment status. See Chapter 37. Instructor Manual for Varcaroliss Canadian Psychiatric Mental Health Nursing Margaret J. Halter, Cheryl L. Pollard, Susan L. Ray, Mary Haase, Sonya Jakubec, Elizabeth M. Varcarolis 9781926648330, 9781771721400

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