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Psychotic disorders are extremely complex illnesses that are influenced by biologic, psychosocial, and environmental circumstances. Some of the disorders require several months of observation and testing before a final diagnosis can be determined. It is beyond the scope of this text to discuss psychotic disorders in detail, but general types of symptoms associated with psychotic disorders will be described.

A delusion is a false or irrational belief that is firmly held despite obvious evidence to the contrary. Delusions may be persecutory, grandiose, religious, sexual, or hypochondriacal. Delusions of reference—in which the patient attributes a special, irrational, and usually negative significance to other people, objects, or events, such as song lyrics or newspaper articles, in relation to self—are common. Delusions may be defined as “bizarre” if they are clearly irrational and do not derive from ordinary life experiences. A common bizarre delusion is the patient’s belief that his or her thinking process, body parts, or actions or impulses are controlled or dictated by some external force.

Hallucinations are false sensory perceptions that are experienced without an external stimulus and seem real to the patient. Auditory hallucinations experienced as voices that are characteristically heard commenting negatively about the patient in the third person, are prominent among patients with schizophrenia. Hallucinations of touch, sight, taste, smell, and bodily sensation also occur.

Disorganized thinking is commonly associated with psychoses. These thought disorders may consist of a loosening of associations or a flight of ideas so that the speaker jumps from one idea or topic to another unrelated one (derailment) in an illogical, inappropriate, or disorganized way. Answers to questions may be obliquely related or completely unrelated (tangentiality). At its most serious, this incoherence of thought extends into pronunciation itself, and the speaker’s words become garbled or unrecognizable. Speech may also be overly concrete (loss of ability to think in abstract terms) and inexpressive; it may be repetitive and may convey little or no real information.

Disorganized behavior is another common characteristic of psychosis. Problems may be noted with any form of goal-directed behavior, leading to difficulties with performing activities of daily living (ADLs), such as organizing meals or maintaining hygiene. The patient may appear markedly disheveled, may dress in an unusual manner (e.g., wearing several layers of clothing, scarves, and gloves on a hot day), or may display clearly inappropriate sexual behavior (e.g., public masturbation) or unpredictable, nontriggered agitation (e.g., shouting, swearing). Disorganized behavior must be distinguished from behavior that is merely aimless or generally not purposeful and from organized behavior that is motivated by delusional beliefs.

Changes in affect may also be symptoms of psychosis. Emotional expressiveness is diminished; there is poor eye contact and reduced spontaneous movement. The patient appears to be withdrawn from others, and the face appears to be immobile and unresponsive. Speech is often minimal, with only brief, slow, monotone replies given in response to questions. There is a withdrawal from areas of functioning that affect interpersonal relationships, work, education, and self-care.

Pharmacologic treatment of psychosis includes several classes of drugs. The most specific are the first- and second-generation antipsychotic agents, but benzodiazepines (see p. 217) are often used to control acute psychotic symptoms. Beta-adrenergic–blocking agents (beta blockers) (e.g., propranolol) (see p. 206), lithium (see p. 271), anticonvulsants (valproic acid, see p. 306; carbamazepine, see p. 296), antiparkinsonian agents (see Chapter 15), and anticholinergic agents (see p. 209) occasionally play a role in controlling the adverse effects of medications used in antipsychotic therapy.

Antipsychotic (also known as neuroleptic) medications can be classified in several ways. Traditionally, they have been divided into phenothiazines and nonphenothiazines. Antipsychotic medications can also be classified as low-potency or high-potency drugs. The terms low potency and high potency refer only to the milligram doses used for these medicines and not to any difference in effectiveness (e.g., 100 mg of chlorpromazine, a low-potency drug, is equivalent in antipsychotic activity to 2 mg of haloperidol, a high-potency drug). Chlorpromazine and thioridazine are low-potency drugs, whereas trifluoperazine, fluphenazine, thiothixene, haloperidol, and loxapine are high-potency drugs. Since 1990, antipsychotic medications have also been classified as typical (first-generation) antipsychotic agents or atypical (second-generation) antipsychotic agents on the basis of their mechanism of action (Table 18-1). The atypical antipsychotic agents are aripiprazole, clozapine, olanzapine, quetiapine, risperidone, and ziprasidone. All of the remaining antipsychotic agents listed in Table 18-1 are typical antipsychotic agents.

Table 18-1

Antipsychotic Agents

GENERIC NAME	BRAND NAME	AVAILABILITY	ADULT DOSAGE RANGE (mg)	MAJOR ADVERSE EFFECTS
				SEDATION	EXTRAPYRAMIDAL SYMPTOMS	HYPOTENSION	ANTICHOLINERGIC EFFECTS
Typical (First-Generation) Antipsychotic Agents
Phenothiazines
chlorpromazine Do not confuse chlorpromazine with chlordiazepoxide, chlorhexidine, chlorpropamide, or chlorthalidone.	Largactil	Tablets: 10, 25, 50, 100, 200 mg Injection: 25 mg/mL	30-1000	+++	++	+++	++
fluphenazine	Modecate	Tablets: 1, 2.5, 5, 10 mg Elixir: 2.5 mg/5 mL Concentrate: 5 mg/mL Injection: 2.5, 25 mg/mL	0.5-40	+	++++	+	+
perphenazine	—	Tablets: 2, 4, 8, 16 mg	12-64	+	+++	+	++
prochlorperazine	Compro, Stemetil	Tablets: 5, 10 mg Injection: 5 mg/mL Suppository: 25 mg	15-150	+	+++	+	+
thioridazine	—	Tablets: 10, 25, 50, 100 mg	150-800	+++	+	+++	+++
trifluoperazine	—	Tablets: 1, 2, 5, 10 mg	2-40	+	+++	+	+
Thioxanthenes
thiothixene	Navane	Capsules: 1, 2, 5, 10, 20 mg	6-60	+	+++	+	+
Nonphenothiazines
haloperidol	Haldol, Novo-Peridol	Tablets: 0.5, 1, 2, 5, 10, 20 mg Concentrate: 2 mg/mL Injection: 5 mg Injection, sustained-release: 50, 100 mg	1-15	+	+++	+	+
loxapine Do not confuse loxapine with Lexapro.	Loxitane, Loxapac	Capsules: 5, 10, 25, 50 mg	20-250	++	+++	++	+
Atypical (Second-Generation) Antipsychotic Agents
aripiprazole	Abilify	Tablets: 2, 5, 10, 15, 20, 30 mg Tablets, orally disintegrating: 10, 15 mg Solution: 1 mg/mL Injection: 7.5 mg/mL	10-15	+	+	+	0
asenapine	Saphris	Tablet, sublingual: 5, 10 mg	5-20	++	++	++	+
clozapine	Clozaril, Rhoxal-clozapine Do not confuse Clozaril with Clinoril or Colazal.	Tablets: 25, 50, 100, 200 mg Tablets, orally disintegrating: 12.5, 25, 100, 150, 200 mg	300-900	+++	+	+++	++
iloperidone	Fanapt	Tablets: 1, 2, 4, 6, 8, 10, 12 mg	12-24	++	+	++	++
olanzapine Do not confuse olanzapine with oxcarbazepine.	Zyprexa Do not confuse Zyprexa with Celexa, Zaroxolyn, or Zyrtec.	Tablets: 2.5, 5, 7.5, 10, 15, 20 mg Tablets, orally disintegrating: 5, 10, 15, 20 mg Injection: 10 mg Injection, sustained release: 210, 300, 405 mg	10-20 30 mg IM	++	+	++	+++
quetiapine	Seroquel, Seroquel XR Do not confuse Seroquel with Symmetrel or Sertraline.	Tablets: 25, 50, 100, 200, 300, 400 mg Tablets, extended release: 50, 150, 200, 300, 400 mg	50-800	++	0	++	0
risperidone	Risperdal Do not confuse Risperdal with estradiol, reserpine, Restoril, risedronate, or ropinirole.	Tablets: 0.25, 0.5, 1, 2, 3, 4 mg Tablets, orally disintegrating: 0.5, 1, 2, 3, 4 mg Solution: 1 mg/mL Injection: 25, 37.5, 50 mg	4-16	+	++	++	+
ziprasidone Do not confuse ziprasidone with zidovudine.	Geodon	Capsules: 20, 40, 60, 80 mg Injection: 20 mg	100-160	+	++	+	++

+, Low; ++, moderate; +++, high.
Available in Canada.

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The typical antipsychotic medications block the neurotransmitter dopamine in the central nervous system (CNS). The atypical antipsychotic agents block dopamine receptors, but they also block serotonin receptors to varying degrees. However, the exact mechanisms whereby these actions prevent psychotic symptoms are unknown. There is substantially more to the development of psychotic symptoms than elevated dopamine levels. There are at least five known types of dopamine receptors and several more types of serotonin receptors in various areas of the CNS. Antipsychotic medications also stimulate or block cholinergic, histaminic, nicotinic, alpha-adrenergic, and beta-adrenergic neurotransmitter receptors to varying degrees, accounting for many of the adverse effects of therapy.

Uses

All antipsychotic medications are equal in efficacy when used in equipotent doses. There is some unpredictable variation among patients, however, and individual patients sometimes show a better response to particular drugs. In general, medication should be selected on the basis of the need to avoid certain adverse effects when dealing with concurrent medical or psychiatric disorders. Despite practice trends, no proof exists that agitation responds best to sedating drugs or that withdrawn patients respond best to nonsedating drugs. Medication history should be a major factor in drug selection. The final important factors in drug selection are the clinically important differences in the frequency of adverse effects. No single drug is least likely to cause all adverse effects; thus, individual response should be the best determinant of which drug is to be used. The atypical antipsychotic agents tend to be more effective in relieving the negative and cognitive symptoms associated with schizophrenia and treating refractory schizophrenia, and they have a much lower incidence of extrapyramidal symptoms (EPSs) and hyperprolactinemia.

The initial goals of antipsychotic therapy are calming the agitated patient who may be a physical threat to himself or herself or to others and beginning the treatment of the psychosis and thought disorder. Combined therapy with benzodiazepines (often lorazepam) and antipsychotic medications allows lower dosages of the antipsychotic medication to be used, reducing the risk of serious adverse effects more commonly seen with higher-dose therapy. Some therapeutic effects, such as reduced psychomotor agitation and insomnia, are observed within 1 week of therapy, but reductions in hallucinations, delusions, and thought disorder often require 6 to 8 weeks of treatment to achieve the full therapeutic effect. Rapid increases in the dosing of antipsychotic medications will not reduce the antipsychotic response time. Patients, families, and the health care team must be informed about giving antipsychotic agents an adequate chance to work before unnecessarily escalating the dosage and increasing the risk of adverse effects.

Clinical Pitfall

During episodes of acute psychosis, the patient is out of touch with reality and often does not understand the need to take medicines that will help stabilize his or her condition. The nurse must ensure that the patient has actually swallowed the medication when it is administered and not just “mouthed” or “cheeked” it. Outpatients often require that medication administration be supervised to ensure adherence to the medication regimen. In some cases, it is necessary to inject long-acting medicines to overcome a patient’s nonadherence problem. After an acute psychotic episode has resolved and the patient is free from overt psychotic symptoms, a decision must be made as to whether maintenance therapy is necessary. This will depend on the diagnosed psychotic disorder and the patient’s tolerance of the adverse effects of the medication. However, most psychotic disorders are treated with lower maintenance dosages to minimize the risk of recurrence of the disorder episodes (Box 18-1).

Box 18-1

Antipsychotic Medicines

Patients who begin antipsychotic drug therapy can expect some therapeutic effects such as reduced psychomotor agitation and insomnia within 1 week of starting treatment. However, reduction in hallucinations, delusions, and thought disorders often requires 6 to 8 weeks for a full therapeutic response to be achieved. Rapid increases in dosages of antipsychotic medications will not reduce the antipsychotic response time, but will increase the frequency of adverse effects.

Antipsychotic medicines may produce extrapyramidal effects. Tardive dyskinesia may be reversible during its early stages, but it becomes irreversible with continued use of the antipsychotic medication. Regular assessment for tardive dyskinesia should be performed for all patients receiving antipsychotic drugs. Older adult patients should be observed for hypotension as well as tardive dyskinesia.

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