Mr. Musk’s drug consumption went well beyond occasional use. He told people he was taking so much ketamine, a powerful anesthetic, that it was affecting his bladder, a known effect of chronic use. He took Ecstasy and psychedelic mushrooms. And he traveled with a daily medication box that held about 20 pills, including ones with the markings of the stimulant Adderall, according to a photo of the box and people who have seen it.

The original Nazis were also big-time drug users.