Porphyria and King George.

The mental illness exhibited by King George III evidenced in the regency crisis of 1788 has inspired several attempts at retrospective diagnosis. The first, written in 1855, thirty-five years after his death, concluded he suffered from acute mania. M. Guttmacher, in 1941, suggested manic-depressive psychosis as a more likely diagnosis. The first suggestion that a physical illness was the cause of King George's mental derangements came in 1966, in a paper "The Insanity of King George III: A Classic Case of Porphyria",^[19] with a follow-up in 1968, "Porphyria in the Royal Houses of Stuart, Hanover and Prussia".^[20] The papers, by a mother/son psychiatrist team, were written as though the case for porphyria had been proven, but the response demonstrated that many, including those more intimately familiar with actual manifestations of porphyria, were unconvinced. Many psychiatrists disagreed with Hunter's diagnosis, suggesting bipolar disorder as far more probable. The theory is treated in Purple Secret,^[21] which documents the ultimately unsuccessful search for genetic evidence of porphyria in the remains of royals suspected to suffer from it.^[22] In 2005 it was suggested that arsenic (which is known to be porphyrogenic) given to George III with antimony may have caused his porphyria.^[23] Despite the lack of direct evidence, the notion that George III (and other members of the royal family) suffered from porphyria has achieved such popularity that many forget that it is merely a hypothesis. In 2010 an exhaustive analysis of historical records revealed that the porphyria claim was based on spurious and selective interpretation of contemporary medical and historical sources.^[24]

Mary Stuart c.1578.

The mental illness of George III is the basis of the plot in The Madness of King George, a 1994 British film based upon the 1991 Alan Bennett play, The Madness of George III. The closing credits of the film include the comment that the illness suffered by King George has been attributed to porphyria and that it is hereditary. Among other descendants of George III theorised by the authors of Purple Secret to have suffered from porphyria (based upon analysis of their extensive and detailed medical correspondence) were his great-great-granddaughter Princess Charlotte of Prussia (Emperor William II's eldest sister) and her daughter Princess Feodora of Saxe-Meiningen. They had more success in being able to uncover reliable evidence that George III's great-great-great-grandson Prince William of Gloucester was reliably diagnosed with variegate porphyria.^{[citation needed]}
It is believed that Mary, Queen of Scots – King George III's great-great-great-great-great-grandmother – also suffered from acute intermittent porphyria, although this is subject to much debate. It is assumed she inherited the disorder, if indeed she had it, from her father, James V of Scotland; both father and daughter endured well-documented attacks that some believe fall within the constellation of symptoms of porphyria.
Vlad III the Impaler was also said to have suffered from acute porphyria, which may have started the notion that vampires were allergic to sunlight.^{[citation needed]}
Other commentators have suggested that Vincent van Gogh may have suffered from acute intermittent porphyria.^[25] It has also been imagined that King Nebuchadnezzar of Babylon suffered from some form of porphyria (cf. Daniel 4).^[26] However, the symptoms of the various porphyrias are so extensive that a wide constellation of symptoms can be attributed to one or more of them.^{[citation needed]}
Paula Frías Allende, the daughter of the Chilean novelist Isabel Allende, fell into a porphyria-induced coma in 1991 which inspired Isabel Allende to write the autobiographical book Paula, dedicated to her daughter.