A Babylonian king, a Dutch Post-Impressionist, a British monarch, and part of hybrid concoction involving a fictional hypnotist all have been suspected of experiencing this ailment. Folklore connects human 'beasts' and the bloodsucking 'undead' with the disease which tends to expell a colourful trait. What is it, who are the famous sufferers, and what is the colour reference to?

lanfranco

This has to be porphyria, sometimes associated with "vampires." The name comes form the Greek word for "purple." George III. van Gogh, and Nebuchadnezzar have been suspected sufferers. Also Svengali, of "Trilby" fame: http://en.wikipedia.org/wiki/Porphyria Nov 29 06, 8:45 PM

peasypod

Yes, certainly is. And the colour reference (albeit the Greek translation 'purple' does fit the criteria of the question) was to the red/pinkish/purple hue of urine from the sufferers. Watched a mind-blowing documentary on Farmer George in the middle of the night, you see. (Things I do when I can't sleep...) A Golden Banana for you. Nov 29 06, 8:56 PM

lanfranco

I should emphasize that Svengali was supposedly conflated with Erik Vachon, a supposed builder of the Paris Opera House, as an inspiration for "Phantom of the Opera". It is Vachon who may have been a porphryia patient, but there is next to no information about this. Nov 29 06, 9:00 PM