 [ Symptoms ] what causes bright blood and a dark brown vomit my father in law is a severe alcoholic and tried to stop cold turkey he is going on day 2 without alcohol and cigarettes and has vomited at least 18 times either bright blood or a very dark brown he refuses to go to the dr so any help would be great thanks for your help [ Disease ] an allergic reaction to what sounds more like some type of infection the sores need to be looked at by a dr an a urine lab test done