"Cocaine, the product of the devil, am I sellin' my soul?"
I wouldn't be surprised if it was true. He wasn't a saint. Just looking at his behavior after prison, I think there's a chance he tried cocaine or something similar. I mean he got skinnier and skinnier as time went on, did more and more work with less and less sleep along with a huge increase in paranoia/aggression/antagonism in general. And just look at the sheer volume of material he left behind in the short span of time he was on DR... You would be naive to deny the possibility, especially considering he took ecstasy while in Italy.
Pac was prescribed Thorazine for post-traumatic stress after the '94 shooting.