Intramuscular drug regimens for acute severe behavioural disturbance in older people

Managing a patient with acute behavioural disturbance is a detailed flowchart for managing a patient with acute behavioural disturbance.

The indications for intramuscular sedation for acute severe behavioural disturbance in older people are detailed here.

Behavioural disturbance in older people is most often associated with delirium or behavioural and psychological symptoms of dementia (BPSD), for which drug therapy is rarely required to manage symptoms—see here for detailed advice about the management of delirium, and here for the management of BPSD. Clinicians who manage acute behavioural disturbance in older people require adequate training in the diagnosis and management of delirium and BPSD, and in nonpharmacological management of acute behavioural disturbance. Only use the drug recommendations for sedation in this topic if the acute behavioural disturbance is severe and there is an imminent risk of harm to the patient or others, and the required expertise and equipment is available.

Most emergency departments and hospitals have protocols for the safe use of parenteral sedation—follow local protocols or consensus state guidelines if available. If intramuscular sedation is used in older people, monitor the patient closely for adverse effects of drugs, including increased risk of falls. For information about minimum monitoring and equipment requirements, see Principles of monitoring a patient with acute behavioural disturbance. In community settings (especially in rural and remote areas) if the minimum monitoring and equipment requirements are not available, a senior clinician needs to make a risk assessment of the situation proportionate to the risk of the sedative drug.

If pharmacological therapy is required in an older person, oral sedation is preferred. Use of parenteral sedation for acute behavioural disturbance in older people should only be considered in exceptional situations, when nonpharmacological interventions have failed, because it is accompanied by a higher relative risk of iatrogenic complications. 

The aim of pharmacological management is to calm the patient with a sufficient initial dose of a sedative drug. Repeated subtherapeutic doses that are inadequate to reduce the patient’s distress and calm their behaviour can prolong the risk of harm to the patient or others. This can also result in larger cumulative doses, or multiple drug administration, both of which increase the risk of adverse drug effects, especially in older people.

When selecting a dose and regimen of a sedative drug for an older person, consider patient factors, such as their level of agitation and distress (eg measured with a Sedation Assessment Tool [SAT] score), age, body size,  sex, comorbidities, drug history, previous response to sedative drugs and response to treatment. In older people with cognitive impairment or communication difficulties, consider the SAT score in the context of the patient’s baseline function and communication style (eg loud outbursts may be usual for individuals with dementia).

Antipsychotic drugs are used to manage acute severe behavioural disturbance in older people for their sedative effects. The sedative effects of antipsychotic drugs occur much sooner than the antipsychotic effects. The evidence to support the efficacy and safety of intramuscular antipsychotics in older people with acute severe behavioural disturbance is limited and further research is required; in older people, adverse drug effects are more likely to be prolonged compared with other adults, increasing potential iatrogenic complications. Intramuscular antipsychotics should only be used in a setting in which staff are trained in the use of intramuscular sedation and its possible complications, and appropriate equipment and expertise to monitor the patient are available.

Antipsychotics, including droperidol and olanzapine, can aggravate motor features in Parkinson disease or Lewy body dementia. In an acute severe behavioural disturbance, if Parkinson disease or Lewy body dementia are suspected, seek expert advice regarding drug choice.

If intramuscular sedation is indicated for an older person with undifferentiated acute severe behavioural disturbance, in combination with nonpharmacological techniques, use:

Repeating the SAT score can be useful to determine whether sedation has been effective or if a repeat dose is needed. Individualise the target SAT score based on patient factors (eg response to nonpharmacological interventions, whether the patient needs to be sedated for investigations) and the ability to maintain patient and staff safety.

If droperidol and olanzapine are not accessible, haloperidol may be used as an alternative; however, haloperidol is less effective and may cause significant extrapyramidal adverse effects and QT-interval prolongation with risk of arrhythmias. Intramuscular chlorpromazine is not recommended as a sedative drug for acute behavioural disturbance because it causes hypotension.

If the antipsychotics above are unavailable or fail to control the situation, seek advice from a senior clinician.

In the rare event that an older person is physically restrained, continue restraint for the shortest duration possible. Titrate any additional doses of intramuscular sedative drugs with extreme caution because people who are restrained are more susceptible to adverse effects.

Always monitor the patient closely for potential adverse effects after administering an intramuscular sedative drug. Older people who have been administered sedation are at increased risk of adverse effects including falls and require continuous clinical observation.