alcohol abuse can produce dementia, sexual impotence, cirrhosis of the liver, and heart disease; and sudden withdrawal can produce severe anxiety, tremors, hallucinations, and life-threatening convulsions. drugs may cause: blackouts, poisoning, overdose and death; physical and psychological dependence; damage to vital organs such as the brain, heart, and liver; inability to learn and remember information; and psychological problems including depression, psychosis, and severe anxiety