Delirium tremens can occur after a period of heavy alcohol drinking; especially, when the person does not eat enough food.
It may also be triggered by head injury, infection, or illness in people with a history of heavy use of alcohol.
It is most common in people who have a history of alcohol withdrawal; especially, in those who drink the equivalent of seven to eight pints of beer (or one pint of "hard" liquor) every day for several months. Delirium tremens also commonly affects those with a history of habitual alcohol use or alcoholism that has existed for more than ten years.
Delirium tremens symptoms occur because of the toxic effects of alcohol on the brain and nervous system. They may be severe and get worse very quickly which is a life-threatening condition that requires immediate medical attention.