I'm worried about my brother. When he gets drunk he starts craving crack. He often drinks hard and smokes at the same time and comes home in this zombified state.

I read on the internet that even though crack alone is deadly, when mixed with alcohol it creates Cocaethylene that can cause sudden death. Does anybody have numbers on this? What are the odds he won't make a binge one day? Is this effect like 0.000001% likely or 10% likely? Or... Please I'd like some answers.