I have always been fascinated by the laundry list of side effects for prescription drugs in commercials, but this one clearly takes the cake ... Angina, nausea, wheezing, belching, coma
He was just on regular old amphetamine. Not to Godwin the thread, but Hitler did Meth every day during the war, via an injection from his personal physician. It certainly didn't help his progressively worsening insanity.
Some people will claim that psychedelics improve creativity. I am one of them. But psychedelics improve creativity by giving people synesthesia, providing years worth of very clear detached associative thinking in hours, and by cleaning out the crud in your psychology so psychological defense mechanisms don't stop you from seeing clearly. I think psilocybin is a better choice for using psychedelics for creativity than LSD, because psilocybin lasts half as long, and so the experience is less likely to be stressful.
Pot changes the perception of time and space, which changes the perception of music, for the better. As Bill Hicks says, if you don't think drugs have done good things, take all your CD's and burn them.
With heroin and successful artists, I think a different type of thing is going on. I think people who are highly sensitive are both better artists, and also more likely to carry around pain and to be aware of the pain around them. They are drawn to heroin because they carry more of the pain around them, and they are good artists because they are highly sensitive. Some people experience vivid musical hallucinations while on opiates, but one has to be predisposed to it. The composer Berlioz used a lot of opium remedies for tooth pain, for example, and much of his music is influenced by musical hallucinations while on opiates. Or, the seventies.
Lest I sound too much like some Timothy Leary hack, let me also say drugs can only enhance your creativity if they do not become such a big part of your life that you act on the ideas you have. Let me also say that creativity requires no drugs. It's perfectly doable to be maximally creative and not use any drugs.