Psychosis is the term used to describe the more severe forms of mental illness. Psychoses are actually a group of mental disorders characterized by marked thought disturbance and an impaired perception of reality. The most common form of psychosis by far is schizophrenia; it is estimated that 1 percent of the world population has this disorder.1 Other psychotic disorders include schizoaffective disorder, delusional disorder, brief psychotic disorder, and shared psychotic disorder. In the past, strong, sedative-like drugs were the primary method of treating patients with psychosis. The goal was to pacify these patients so they were no longer combative and abusive to themselves and others. These drugs were commonly referred to as major tranquilizers and had the obvious disadvantage of sedating a patient so that his or her cognitive and motor skills were compromised.
As researchers learned more about the neurochemical changes involved in psychosis, pharmacologists developed drugs to specifically treat disorders rather than simply sedate the patient. These antipsychotic drugs, or neuroleptics as they were sometimes called in the past, represented a major breakthrough in the treatment of schizophrenia and other psychotic disorders. Today, antipsychotic drugs often have positive effects on the quality of life in people with psychosis and have enabled many of them to live in the community rather than be institutionalized for long periods of time.2,3 This observation does not imply that these drugs cure schizophrenia. Schizophrenia and other psychoses are believed to be incurable, and psychotic episodes can recur throughout a patient's lifetime. But these drugs can normalize the patient's behavior and thinking during an acute psychotic episode, and maintenance dosages are believed to help prevent the recurrence of psychosis. Consequently, the ability of people with psychosis to take care of themselves and cooperate with others is greatly improved.
Physical therapists and occupational therapists frequently encounter patients taking antipsychotics. Therapists employed in a psychiatric facility will routinely treat patients taking these medications. Therapists who practice in nonpsychiatric settings may still encounter these patients for various reasons. For instance, a patient on an antipsychotic medication who sustains a fractured hip may be seen at an orthopedic facility. Consequently, knowledge of antipsychotic pharmacology will be useful to all rehabilitation specialists.
Because of the prevalence of schizophrenia, this chapter concentrates on the treatment of this psychotic disorder. Also, the pathogenesis and subsequent treatment of other forms of psychosis are similar to those of schizophrenia, so we use this specific condition as an example of the broader range of psychotic conditions.
The Diagnostic and Statistical Manual of Mental Disorders lists several distinct criteria necessary for a diagnosis of schizophrenia,4 including delusions, hallucinations, disorganized speech, and grossly disorganized or catatonic behavior. Also, a decreased level of function in work, social relations, and self-care may be present. Other factors include the duration of these and additional symptoms (at least ...