Text adapted from "The patient with Psychosis" in Psychiatry in primary care by George Foussias and Z. Jeff Daskalakis (CAMH, 2019).
The following section focuses on treating psychotic symptoms in the context of schizophrenia or schizoaffective disorder. The same general principles apply for treating psychosis in the context of other illnesses; however, the underlying illness must be addressed (e.g., psychosis in the context of delirium, major depressive episode with psychotic features).
Electroconvulsive Therapy (ECT) in combination with antipsychotic medication may offer some benefit for treatment-resistant psychotic symptoms.
The goal of acute treatment for a patient with psychosis is full remission of symptoms and return to baseline function. Acute treatment involves the following components:
- diagnostic assessment
- assessment of the potential for danger to self or others
- engagement of the patient and caregivers in the treatment process, which includes discussing risks and benefits of treatment
- initiation of pharmacological treatment as soon as possible.
Second-generation antipsychotic medications (SGAs) are the first-choice treatments, particularly for previously unmedicated patients who are particularly sensitive to acute extrapyramidal and sedative side-effects caused by antipsychotics.
The SGAs, including olanzapine, risperidone, paliperidone, quetiapine, ziprasidone, aripiprazole, asenapine and lurasidone, offer improved tolerability, particularly with regard to extrapyramidal symptoms, compared with first-generation antipsychotics (FGAs) (see Table 1).
Usually there is not one definite choice of medication for any given patient because there is much individual variability in efficacy and side-effects. The choice of antipsychotic is based primarily on individual profiles of efficacy and tolerability:
- All SGAs, except clozapine, appear to be equally effective in treating psychosis in schizophrenia, with some recent evidence suggesting a slight advantage for olanzapine.
- SGAs, except clozapine, and FGAs appear to be equally effective in treating schizophrenia and schizoaffective disorder.
- Clozapine has unique efficacy in treatment-resistant schizophrenia and schizoaffective disorder (patients who have not benefited from previous trials of two antipsychotics).
- All antipsychotics carry a risk of extrapyramidal symptoms and tardive dyskinesia, although the risk appears to be higher with FGAs than SGAs. Of the SGAs, the risk of extrapyramidal symptoms appears to be highest with risperidone and paliperidone.
- All antipsychotics carry a risk of weight gain and metabolic abnormalities, although the risk appears to be higher with SGAs, particularly olanzapine, quetiapine and clozapine.
- Risperidone and paliperidone are the SGAs most commonly associated with elevated prolactin levels and subsequent amenorrhea and sexual dysfunction.
- Ziprasidone carries a potential risk of QTc prolongation and, as such, is contraindicated in patients with a prolonged QTc interval.
- Clozapine carries a risk of agranulocytosis, which requires regularly monitoring white blood cell and neutrophil counts (weekly for the first six months, every two weeks for the next six months, monthly thereafter). The risk is approximately one percent, and appears to be greatest in the early stages of treatment. Clozapine commonly causes constipation (in about 14 percent of patients), and appropriate monitoring and intervention is recommended.
- Treatment of schizoaffective disorder typically involves a combination of an antipsychotic and a medication that targets the mood disturbance.
See Table 2 for recommended medication monitoring guidelines.
ECT in combination with antipsychotic medication may offer some benefit for treatment-resistant psychotic symptoms.