This is a relatively common psychiatric cause in our experience. Schizophrenia, especially the paranoid variety. The hallmark is said to be disorientation, a fluctuating level of consciousness and abnormal vital signs. Our experience is that this is more a problem of the older, in-patient than the emergency department patient. Mental retardation or dementia.
Diagnosis is usually well known to the caregivers and is often obvious to the medical personnel.
Drug and alcohol abuse Drug and alcohol abuse is quite a common cause of violent or aggressive behaviour, in our experience. Personality or behavioural disorders People with antisocial personalities or borderline personality disorders can be quite noisy and aggressive. These people usually are not classed as having psychiatric illnesses. These individuals can actually get quite aggressive. As in any problem, forewarned is forearmed.