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CHAPTER 15 ■ Schizophrenia Spectrum and Other Psychotic Disorders
there was a significant worsening of symptoms over the course of a year in patients who did not continue on medication. As mentioned earlier, the efficacy of antipsychotic medications is enhanced by adjunct psychosocial therapy. Because the psychotic manifestations of the illness subside with use of the drugs, clients are generally more cooperative with the psychosocial therapies. However, although the sedative effects are relatively immediate, it takes several weeks for the antipsychotics to effectively treat positive symp- toms, a fact that often leads to discontinuation of the medication. Clients and families need to be educated about the importance of waiting, often for several weeks, to determine whether the drug will be effective. These medications are classified as either typical antipsychotics (first generation with more dopami- nergic activity) or atypical antipsychotics (second generation with more serotonergic activity). In 2019 a newer novel drug (that does not bind to D 2 or 5-HT 2A ) was given U.S. Food and Drug Adminis- tration (FDA) “breakthrough therapy” approval for investigation, and early results indicate that it may be effective in treating both positive and negative symp- toms (Ernst, 2019). Examples of commonly used antipsychotic agents are presented in Table 15–3. A description of these medications follows. More detailed information is available in Chapter 4, “Psychopharmacology.” Indications Antipsychotic medications are used in the treatment of schizophrenia and other psychotic disorders. Selected agents are used in the treatment of bipolar mania (olanzapine, aripiprazole, chlorpromazine, quetiapine, risperidone, asenapine, ziprasidone). Action Typical antipsychotics work by blocking postsynaptic dopamine (D 2 ) receptors in the basal ganglia, hypo- thalamus, limbic system, brainstem, and medulla. They also demonstrate varying affinity for cholin- ergic, alpha 1 -adrenergic, and histaminic receptors. Antipsychotic effects may also be related to inhibi- tion of dopamine-mediated transmission of neural impulses at the synapses. Atypical antipsychotics are weaker dopamine receptor antagonists than the conventional anti- psychotics but are more potent antagonists of the serotonin (5-hydroxytryptamine) type 2A (5-HT 2A ) receptors. They also exhibit antagonism for cholin- ergic, histaminic, and adrenergic receptors.
Positive symptoms respond relatively well to treatment with both typical (first generation) and atypical (second generation) antipsychotic med- ication. Boland and Verduin (2022) identify that positive symptoms tend to become less severe over time, whereas the negative or “deficit” symptoms are socially debilitating and may increase in sever- ity. Atypical antipsychotics have been advanced as being somewhat more effective than first genera- tion antipsychotics in treating negative symptoms (particularly cariprazine), but researchers continue to search for medications that will specifically treat the several cognitive deficits that are most problem- atic for patients with schizophrenia. These deficits include memory, attention, language, and executive functions, and they can dramatically impact an indi- vidual’s overall functional ability. A detailed discussion of contraindications, pre- cautions, side effects, and drug interactions associ- ated with antipsychotic medications is available in Chapter 4, “Psychopharmacology.” Side Effects The effects of these medications are related to block- age of a number of receptors for which they exhibit various degrees of affinity. Blockade of the dopamine receptors is thought to be responsible for controlling positive symptoms of schizophrenia. Dopamine block- ade also results in extrapyramidal symptoms (EPS) and prolactin elevation (galactorrhea; gynecomastia). (A list of medications commonly used to treat EPS is included in Table 15–4.) Cholinergic blockade causes anticholinergic side effects (dry mouth, blurred vision, constipation, urinary retention, and tachycardia). Blockage of the alpha 1 -adrenergic receptors produces dizziness, orthostatic hypotension, tremors, and reflex tachycardia. Histamine blockade is associated with weight gain and sedation. The plan of care should include monitoring for the side effects from antipsychotic medications and educating the patient and family about safety precau- tions when taking antipsychotic medication. (A list of side effects and relevant nursing interventions is included in Chapter 4, “Psychopharmacology.”) There have been two recent and novel develop- ments in psychopharmacological treatments for patients with schizophrenia. The first is a formula- tion of aripiprazole (AbilifyMyCite) with a tracking sensor that allows the client (and others) to monitor whether the medication was taken. Approved in late 2017, this formulation has spurred controversy and debate about the benefits versus the potential intru- siveness of such a monitoring device. The second
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