PKD was insane. He fried his brains and was seeing pink beams.I was asking about meth on "Under the Dome" novel thread because meth is mentioned in the book as a kind of "apple of knowledge" , opening eyes to wonderful realms.
SK did drugs for whatever reasons (after publishing Carrie and having to cope with the fear of being an one-book author) , but I am not sure if he used meth.
Philip K Dick used meth to stay awake and write lots of short sci-fi stories during a period when he needed money from his writing.
PKD might have suffered the consequences later on in life and his life might have been shortened due to his drugs usage in his 20s and 30s.