If he used cocaine heavily over a period of time, I would guess that even now he would be in danger of a heart attack. That, plus his chain smoking would be a deadly combination. But, I don't know of any reports that said that he was anything more than an occasional user of cocaine.
What "reports" might that be?
All the "reports" are based on Obama's version. (yeah, I'm sure he didn't downplay his history of drug abuse).
There is of course, Larry Sinclair's "report", that says Obama smoked crack cocaine.
Knock yourself out, keep citing all those "reports".