24 Jun MSA atypical antipsychotics
The Medicines Control Council wishes to inform prescribers of increased risks of cerebrovascular adverse events (including strokes and transient ischaemic attacks) and mortality associated with the use of atypical antipsychotics in elderly patients with dementia.
The atypical antipsychotics to which this medicine safety alert refers include clozapine, risperidone, olanzapine, quetiapine, ziprasidone and aripiprazole. Antipsychotics have been frequently used to treat behavioural and psychological disturbances in dementia such as agitation, aggression and psychosis in the elderly. This practice is common even in countries where the indication is not approved by the regulatory authority.
In South Africa only risperidone is indicated for treating behavioural disturbances associated with dementia. Recent advisories from other regulatory authorities suggest a potential increased risk of cerebrovascular adverse events and mortality with atypical antipsychotics. Although there is limited data available for some of these agents, the warnings have been applied to all the atypical antipsychotics as the findings appear to have been consistent across studies and chemical classes.
Subsequent to these warnings, published studies have also shown an increased risk of morbidity and mortality associated with the use of conventional antipsychotics (e.g. phenothiazines and haloperidol).
Healthcare practitioners are therefore advised of the following:
1. Before prescribing, clinicians are advised to carefully assess the risks and benefits of the use of atypical antipsychotics in elderly patients with dementia, taking into account risk predictions for stroke in the individual patient (e.g. hypertension, diabetes, current smoking, atrial fibrillation, and age > 80 years).
2. Where the use of antipsychotics in the elderly is considered essential, the lowest effective dose should be used. These patients should be carefully monitored to avoid or reduce hypotension, gait disturbances, oversedation and complications associated with hyperglycaemia.
3. Olanzapine, quetiapine, ziprasidone, clozapine and aripiprazole are not indicated for use in elderly patients with dementia exhibiting behavioural disturbances.
4. Clinicians should report any suspected adverse drug reactions to the Medicines Control Council’s National Adverse Drug Event Monitoring Centre (NADEMC) at telephone: (021) 448 1618 and fax: (021) 448 6181.