The agitated or aggressive patient: a case-based approach

The case

An older adult is brought to an emergency department by relatives who say he has become confused and "not himself" over two days. In the waiting room he is restless, shouting, and pushing away staff who approach him. His family insist he is normally gentle and calm. It would be easy to label this as challenging behaviour and simply wait for it to settle. In UK practice, though, a sudden change like this in someone who is usually well is treated as a warning sign of physical illness until proven otherwise. The first priorities are keeping the person and others safe, and beginning to work out why the change has happened.

Safety and de-escalation first

Before anything else, staff make the environment safe: giving the person space, removing obvious hazards, and ensuring colleagues know what is happening and that help is nearby. The first-line approach to agitation is always de-escalation, not restraint. This means a calm voice, open body language, one person leading the conversation, listening to concerns, offering simple choices, and reducing noise and crowding. Physical restraint or medicines to calm someone are a last resort, used only when there is a serious risk of harm and after less forceful steps have failed. The aim is to lower distress enough to allow assessment, while protecting the person's dignity and the safety of everyone around them.

Think organic causes

A crucial rule is to look for an "organic" (physical) cause of agitation before assuming it is psychiatric, especially when the change is sudden. Delirium — an acute confused state — is common and has many triggers: infection, low blood sugar, low oxygen, dehydration, constipation, pain, a full bladder, head injury, alcohol or drug withdrawal, and side effects of medicines. In an older person, a urine or chest infection can present mainly as confusion. Checking a blood sugar level is one of the quickest and most important early steps, because low glucose can cause aggression and is rapidly reversible. Missing a physical cause can be dangerous, so clinicians actively hunt for one rather than reaching for a behavioural label.

The structured assessment

Once it is safe, assessment follows a familiar order: airway, breathing, circulation, disability and exposure. Vital signs — temperature, pulse, blood pressure, breathing rate and oxygen level — are measured alongside blood glucose. A collateral history from family is gold dust: what is normal for this person, how quickly they changed, recent illnesses, medicines, alcohol or drug use, and any falls or head knocks. Examination and simple tests such as blood tests, urine testing and sometimes a brain scan help pin down the cause. Throughout, staff weigh the person's mental capacity to make decisions and act in their best interests, using the least restrictive option, while documenting clearly what was seen and done.

Red flags and what happens next

Certain features point to a serious, time-critical cause and prompt urgent action: a very high or low temperature, low oxygen, a very high or low blood sugar, a severe headache, weakness on one side, a stiff neck, drowsiness, or agitation following a head injury. New confusion in an older person is itself a red flag. Once a cause is found — an infection, low glucose, withdrawal or a brain problem — treatment is directed at it, and the agitation usually eases as the underlying illness is corrected. Families are kept informed. The overarching message is that agitation is a symptom to be explained, not simply a behaviour to be contained.