Yes, suddenly stopping alcohol intake after long-term heavy drinking can cause a dangerous condition called delirium tremens (DTs), which can be life-threatening. Symptoms of DTs can include severe confusion, rapid heartbeat, high blood pressure, fever, and seizures. Additionally, alcohol withdrawal can also cause other serious complications such as dehydration, electrolyte imbalances, and aspiration pneumonia, which can also be potentially fatal. It is recommended to seek medical help and supervision when quitting drinking after a prolonged period of heavy alcohol use to manage and prevent these dangerous complications.