Delirium is a common syndrome affecting many elderly patients not only admitted into acute medical wards but also in the community. The syndrome of delirium can be defined as acute brain failure associated with autonomic dysfunction, motor dysfunction and homeostatic failure. Delirium develops over a short period of time (hours to days) and fluctuates throughout the course of the day. It is characterised by a reduction in clarity of awareness, inability to focus, distractibility and change in cognition.