I wouldn't be too surprised if such a thing existed. There have also been hints about it from other people.

In regards to her death...I've rarely heard of people mixing all three of those drugs. Rarely do people mix LSD with alcohol in my experience. LSD kinda cancels out the alcohol. You don't really feel drunk. Coke is a stimulant, when combined with alcohol, can make you think you can drink more, so I would think that combining the three would make you not aware of how much you were drinking. Perhaps a recipe for drinking yourself to death. But perhaps that was the point.