Source of Information:
http://www.bnf.org.uk/
Printed from: Joint Formulary Committee. British National Formulary. 51 ed. London: British Medical Association and Royal Pharmaceutical Society of Great Britain; 2006.
acute and chronic psychoses, mania
[see notes below]
(including advice on atypical antipsychotics and stroke); Parkinson's disease; pregnancy (Appendix 4); hepatic impairment (Appendix 2), renal impairment (Appendix 3)
see notes above; also insomnia, agitation, anxiety, headache; less commonly drowsiness, impaired concentration, fatigue, blurred vision, constipation, nausea and vomiting, dyspepsia, abdominal pain, hyperprolactinaemia (with galactorrhoea, menstrual disturbances, gynaecomastia), sexual dysfunction, priapism, urinary incontinence, tachycardia, hypertension, oedema, rash, rhinitis; cerebrovascular accident, neutropenia and thrombocytopenia have been reported; rarely seizures, hyponatraemia, abnormal temperature regulation, and epistaxis
Side-effects of the atypical antipsychotics include weight gain, dizziness, postural hypotension (especially during initial dose titration) which may be associated with syncope or reflex tachycardia in some patients, extrapyramidal symptoms (usually mild and transient and which respond to dose reduction or to an antimuscarinic drug), and occasionally tardive dyskinesia on long-term administration (discontinue drug on appearance of early signs). Hyperglycaemia and sometimes diabetes can occur, particularly with clozapine and olanzapine; monitoring weight and plasma glucose may identify the development of hyperglycaemia. Neuroleptic malignant syndrome has been reported rarely.
While atypical antipsychotics have not generally been associated with clinically significant prolongation of the QT interval, they should be used with care if prescribed with other drugs that increase the QT interval. Atypical antipsychotics should be used with caution in patients with cardiovascular disease, or a history of epilepsy; they should be used with caution in the elderly; interactions: Appendix 1 (antipsychotics).
Olanzapine and risperidone are associated with an increased risk of stroke in elderly patients with dementia. The CSM has advised:
risperidone or olanzapine should not be used for treating behavioural symptoms of dementia;
for acute psychotic conditions in elderly patients with dementia, risperidone should be limited to short-term use under specialist advice; olanzapine is not licensed for acute psychoses;
the possibility of cerebrovascular events should be considered carefully before treating any patient with a history of stroke or transient ischaemic attack; risk factors for cerebrovascular disease (e.g. hypertension, diabetes, smoking, and atrial fibrillation) should also be considered.
Atypical antipsychotics may affect performance of skilled tasks (e.g. driving); effects of alcohol are enhanced.
Withdrawal of antipsychotic drugs after long-term therapy should always be gradual and closely monitored to avoid the risk of acute withdrawal syndromes or rapid relapse.