Sounds like Erdős might have had ADD/ADHD or something similar, and amphetamines was his medication. Edit: Never read about Erdős before and came across this:

Sounds like Erdős might have had ADD/ADHD or something similar, and amphetamines was his medication. Edit: Never read about Erdős before and came across this: "Erdős published around 1,500 mathematical papers during his lifetime, a figure that remains unsurpassed". Maybe he was just a functional addict :)