SCHIZOPHRENIA - A common and serious mental disorder characterized by loss of contact with reality (psychosis), hallucinations (false perceptions), delusions (false beliefs), abnormal thinking, flattened affect (restricted range of emotions), diminished motivation, and disturbed work and social functioning.
Diagnosis - No definitive test for schizophrenia exists. Diagnosis is based on a comprehensive assessment of clinical history, symptoms, and signs. Information from ancillary sources, such as family, friends, and teachers, is often important in establishing chronology of illness onset. According to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), two or more characteristic symptoms (delusions, hallucinations, disorganized speech, disorganized behavior, negative symptoms) for a significant portion of a 1-mo period are required for the diagnosis, and prodromal or attenuated signs of illness with social, occupational, or self-care impairments must be evident for a 6-mo period that includes 1 mo of active symptoms.
Psychotic disorders due to physical disorders or associated with substance abuse and primary mood disorders with psychotic features must be ruled out by clinical examination and history. Additionally, laboratory tests can rule out underlying medical, neurologic, and endocrine disorders that can present as psychosis (eg, vitamin deficiencies, uremia, thyrotoxicosis, electrolyte imbalance).
Treatment - Patients with schizophrenia tend to develop psychotic symptoms an average of 12 to 24 mo before presenting for medical care. The time between onset of psychotic symptoms and first treatment, termed duration of untreated psychosis, correlates with the rapidity of initial treatment response, quality of treatment response, and severity of negative symptoms. When treated early, patients tend to respond more quickly and fully. Without prophylactic antipsychotic drugs, 70 to 80% of patients who have had a schizophrenia episode have a subsequent episode during the next 12 mo. Continuous prophylactic antipsychotic drugs can reduce the 1-yr relapse rate to about 30%.
General goals of treatment are to reduce the severity of psychotic symptoms, prevent recurrences of symptomatic episodes and associated deterioration of functioning, and help patients function at the highest level possible. Antipsychotic drugs, rehabilitation with community support services, and psychotherapy are the major components of treatment.
Antipsychotic drugs: Conventional antipsychotic (neuroleptic) drugs include chlorpromazine, fluphenazine, haloperidol, loxapine, mesoridazine, molindone, perphenazine, pimozide, thioridazine, thiothixene, and trifluoperazine (see Table 1931). These drugs are characterized by their affinity for the dopamine 2 receptor and can be classified as high, intermediate, or low potency. Different drugs are available in tablet, liquid, and short- and long-acting IM preparations. A specific drug is selected primarily based on adverse effects, required route of administration, and the patient's previous response to the drug.
Two conventional antipsychotic drugs are available as long-acting depot preparations (see Table 1932). These preparations are useful mainly for ruling out covert drug noncompliance as a cause of symptom exacerbation and lack of drug response. They may also help patients who cannot reliably take daily oral drugs. About 30% of patients with schizophrenia do not respond to conventional antipsychotic drugs (treatment refractory). They may respond to atypical antipsychotic drugs, such as Clozapine, which is effective in up to 50% of patients who are resistant to conventional antipsychotic drugs.
Newer atypical antipsychotic drugs currently or soon to be available are risperidone, olanzapine, quetiapine, sertindole, and ziprasidone. For most patients with schizophrenia, these drugs are more effective and have fewer adverse effects than conventional antipsychotics.
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