The many illnesses of Charles Darwin

DelanceyPlace.com has a selection from My Age of Anxiety by Scott Stossel:

Based on his diaries and letters, it is reasonable to conclude that Charles Darwin (photo) spent a full third of his daytime hours after his voyage on the Beagle either vomiting or lying in bed. That includes the period during which he wrote On the Origin of Species. The cause remains unknown.
Observers, going back to Aristotle, have noted that nervous dyspepsia and intellectual accomplishment often go hand in hand. Sigmund Freud's trip to the United States in 1909, which introduced psychoanalysis to this country, was marred (as he would later frequently complain) by his nervous stomach and bouts of diarrhea. Many of the letters between William and Henry James, first-class neurotics both, consist mainly of the exchange of various remedies for their stomach trouble.
But for debilitating nervous stomach complaints, nothing compares to that which afflicted poor Charles Darwin, who spent decades of his life prostrated by his upset stomach. In 1865, he wrote a desperate letter to a physician named John Chapman, listing the array of symptoms that had plagued him for nearly thirty years:

Age 56-57. For twenty-five years, extreme spasmodic daily & nightly flatulence: occasional vomiting, on two occasions prolonged during months. Vomiting preceded by shivering, hysterical crying, dying sensations or half-faint & copious very pallid urine. Now vomiting & every passage of flatulence preceded by ringing of ears, treading on air, & vision .... Nervousness when Emma (his wife) leaves me.

Even this list of symptoms is incomplete. At the urging of another doctor, Darwin had, from 1 July 1849, to 16 January 1855, kept a 'Diary of Health,' which eventually ran to dozens of pages, and listed such complaints as chronic fatigue, severe stomach pain and flatulence, frequent vomiting, dizziness ('swimming head,' as Darwin described it), trembling, insomnia, rashes, eczema, boils, heart palpitations and pain, and melancholy.
Darwin was frustrated that dozens of physicians, beginning with his own father, had failed to cure him. By the time he wrote to Dr. Chapman, Darwin had spent most of the past three decades, during which time he'd struggled heroically to write On the Origin of Species, housebound by general invalidism. Based on his diaries and letters, it's fair to say he spent a full third of his daytime hours, since the age of twenty-eight, either vomiting or lying in bed.
Chapman prescribed the application of ice to the spinal cord for almost all diseases of nervous origin. He came out to Darwin's country estate in late May of 1865, and Darwin spent several hours each day over the next several months encased in ice; he composed crucial sections of The Variation of Animals and Plants Under Domestication with ice bags packed around his spine.
The treatment didn't work. The 'incessant vomiting' continued. So, while Darwin and his family enjoyed Chapman's company ('We liked Dr. Chapman so very much we were quite sorry the ice failed for his sake as well as ours', Darwin's wife wrote), by July of 1865 they had abandoned the treatment and sent the doctor back to London.
Chapman was not the first doctor to fail to cure Darwin, and he would not be the last. To read Darwin's diaries and correspondence is to marvel at the more or less constant debilitation he endured after he returned from the famous voyage of the Beagle in 1836. The medical debate about what, exactly, was wrong with Darwin has raged for a hundred and fifty years. The list proposed during his life and after his death is long: amoebic infection, appendicitis, duodenal ulcer, peptic ulcer, migraines, chronic cholecystitis, 'smouldering hepatitis', malaria, catarrhal dyspepsia, arsenic poisoning, porphyria, narcolepsy, 'diabetogenic hyper-insulism', gout, 'suppressed gout', chronic brucellosis (endemic to Argentina, which the Beagle had visited), Chagas' disease (possibly contracted from a bug bite in Argentina), allergic reactions to the pigeons he worked with, complications from the protracted seasickness he experienced on the Beagle, and 'refractive anomaly of the eyes'. I've just read an article, 'Darwin's Illness Revealed', published in a British academic journal in 2005, that attributes Darwin's ailments to lactose intolerance. But a careful reading of Darwin's life suggests that the precipitating factor in every one of his most acute attacks of illness was anxiety." 

Rico says that being a genius can be tiresome... (And, before the invention of drugs to treat anxiety, very tiresome).