Following the first psychotic episode, antipsychotic medication is usually stopped by the patient after 1-2 years, although long-term therapy is the rule for patients with recurrent illness. Antipsychotics prevent relapse in patients with remitted positive and mood symptoms, and maintenance treatment helps to reduce symptoms in patients with chronic illness. These drugs enable many patients who previously would have been institutionalised to live in the community.
The most commonly used conventional antipsychotics in the long-term treatment of psychoses are high-potency oral antipsychotics, such as haloperidol and trifluoperazine or depot formulations, such as flupenthixol. The major drawback with conventional antipsychotics is their tendency to produce extrapyramidal adverse effects at effective doses. These include dystonias, parkinsonism, akathisia and tardive dyskinesia, a disfiguring, stigmatising and often irreversible neurological disorder.
Atypical antipsychotics are a diverse group of drugs with a lower risk of extrapyramidal adverse effects at therapeutically effective doses. Some atypicals may be more effective than conventional antipsychotics in long-term treatment. Clozapine is particularly effective for treatment resistant cases. While its toxicity restricts initiation of treatment to specialist centres, increasingly general practitioners are involved in long-term care and monitoring of patients on clozapine therapy. Risperidone has shown superior efficacy to haloperidol in long-term prevention of relapse.3Recently, high-dose olanzapine was shown to have greater effectiveness than conventional and other atypical antipsychotics (apart from clozapine) in terms of discontinuation rates over an 18-month period.4
While reducing problems with extrapyramidal adverse effects, atypicals have caused other problems such as postural hypotension, weight gain and hyperglycaemia. Each drug seems to have adverse effects which are particular problems, for example, clozapine can cause neutropenia, agranulocytosis and myocarditis. Olanzapine frequently causes considerable weight gain and increases glucose and lipids which can lead to hyperlipidaemia and diabetes.4Although weight gain is less of a problem with risperidone, it may cause sexual dysfunction and amenorrhoea due to hyperprolactinaemia. Quetiapine may cause mild weight gain, while amisulpride and aripiprazole are generally well tolerated in long-term treatment (although aripiprazole can initially cause troubling nausea and restlessness).
Table 1
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Monitoring the physical health of patients with psychosis *
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Assessment
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Checks for:
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History and examination, including:
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- cardiovascular
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- evidence of arrhythmias and ischaemic heart disease
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- neurological
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- tardive dyskinesia, akathisia and tremor
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- funduscopic exam through undilated pupils
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- lens opacities and retinal pigmentation
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Weight: calculate body mass index (weight/height2)
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changes in weight
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Random blood glucose
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diabetes (increased risk with some atypical antipsychotics)
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Cholesterol and triglycerides
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cardiovascular disorders (increased risk)
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Vitamin B12 and folate
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nutritional deficiency
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Calcium, phosphate
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drug effects
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Full blood exam, erythrocyte sedimentation rate
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infection, nutritional deficiency, anaemia
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Liver function
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alcohol and other drug effects
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ECG
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drug effects, cardiovascular disease
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Drug screen
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illicit drug use
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Other investigations as appropriate, e.g.
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- thyroid function
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- effects of lithium
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- therapeutic drug monitoring
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- effects of lithium
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- echocardiography
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- cardiomyopathy (clozapine)
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- cervical smear
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* suggested monitoring at initial examination and repeated at 6–12 month intervals depending on risk
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