Charles Darwin's illness
In 1837, soon after returning from the flve-year expedition of H.M.S. Beagle, Charles Darwin developed a mysterious illness, which continued almost to his death, 45 years later; Charles Darwin's illness has been the subject of speculation ever since.
Darwin was just 28 when showed the first signs of the disease. In letters, he complained of being unwell, with a swimming of the head, depression and trembling, and he wrote that anything which "flurries me completely knocks me up afterwards and brings on violent palpitation of the heart." These attacks restricted Darwin's subsequent travel and attendance at meetings; he declined the Geological Society’s secretaryship, and the anxiety he felt after speaking at the Linnaean Society in London brought on 24 hours of vomiting. In 1842, Darwin and his wife, Emma, moved to the country to live a quiet life. He avoided social gatherings and left his home only in the company of his wife, and never left England again.
Commentators have noted that Darwin's illness enabled him to avoid the distractions of lectures, teaching, and public appearances; according to Sir George Pickering, "without that illness, the great work would not have been done, or done in such splendid style."
Darwin's medical complaints included intestinal, circulatory and nervous symptoms. His complaints of indigestion suggest upper intestinal tract disease, but are not characteristic of any disease in particular. Darwin often referred his "palpitations", which might have been an arrhythmia; but precordial pain is not often mentioned and no shortness of breath or fluid retention was ever noted. His nervous symptoms are mentioned repeatedly in letters but never in much detail. He seems to have had good days and bad days, and the main feature of the bad days was exhaustion.
Darwin's own doctors seem to have been helpless; some thought him a hypochondriac, and the suspicion that they did so caused Darwin real distress. He was examined by a succession of famous physicians, including his own father, Robert Waring Darwin, but little is known about their diagnoses or recommended treatments.
"You are very kind in your inquiries about my health; I have nothing to say about it, being always the same, some days better and some days worse. I believe I have not had one whole day, or rather night, without my stomach having been greatly disordered, during the last three years, and most days great prostration of strength: thank you for your kindness; many of my friends, I believe, think me a hypochondriac." Darwin's letter to his friend Sir Joseph Dalton Hooker, an English botanist and traveller, written in 1845:
By March 28, 1849, Darwin felt that he was dying:
"I was not able to do anything one day out of three, & was altogether too dispirited to write to you or to do anything but what I was compelled. I thought I was rapidly going the way of all flesh." 
Darwin and Dr Gully
Darwin diagnosed his own condition as "nervous dyspepsia" and on the advice of a cousin, he traveled with his family over 100 miles to the clinic and “water-cure” spa of Dr James Manby Gully at Malvern in Kent on March 10, 1849. Dr Gully had written a popular book called The Water Cure in Chronic Disease and identified himself as a homeopathic physician.
Darwin was skeptical of homeopathy, and on March 19 he wrote: “I grieve to say that Dr Gully gives me homeopathic medicines three times a day, which I take obediently without an atom of faith.” But after two weeks of treatment, including sweating induced by Gully's own invention, the ‘lamp bath’  Darwin wrote "I much like and think highly of Dr Gully." On March 28, he had not vomited for 10 days, a rare experience for him. On April 19 he wrote:
“I now increase in weight, have escaped sickness for 30 days, which is thrice as long an interval, as I have had for last year; & yesterday in 4 walks I managed seven miles! I am turning into a mere walking and eating machine.”
Darwin stayed at Gully's clinic for four months. Shortly after returning home, he re-experienced his nausea, and he continued to experience digestive problems throughout his life, though he no longer experienced many of his other symptoms (fainting spells, spots before his eyes, and extensive boils) and was able to resume working. Despite the benefits that Darwin seemed to experience, he remained skeptical about homeopathy. Three months after leaving Gully’s clinic, he wrote:
- "You speak about Homœopathy; which is a subject which makes me more wrath, even than does Clairvoyance: clairvoyance so transcends belief, that one's ordinary faculties are put out of question, but in Homœopathy common sense & common observation come into play, & both these must go to the Dogs, if the infinitesimal doses have any effect whatever. How true is a remark I saw the other day by Quetelet, in respect to evidence of curative processes, viz that no one knows in disease what is the simple result of nothing being done, as a standard with which to compare Homœopathy & all other such things. It is a sad flaw, I cannot but think in my beloved Dr Gully, that he believes in everything when his daughter was very ill, he had a clairvoyant girl to report on internal changes, a mesmerist to put her to sleep, an homœopathist, viz Dr. Chapman; & himself as Hydropathist! & the girl recovered.” 
According to Darwin's son, Francis, Gully's cures had only a transient effect, though the significant elimination of many of Darwin's serious symptoms disappeared shortly after he began Gully's regiment of water-cure, homeopathic medicines, and clairvoyant readings. However, when, in 1851, Darwin's daughter Annie had persistent indigestion he took her to Gully's clinic on 24 March. Gully repeatedly reassured them that she was recovering, but Annie died on 23 April.
After Gully retired, Gully hired a medical doctor who practiced homeopathy and water-cure to take over his clinic, Dr. James Smith Ayerst. Evidence of Darwin's affection for Dr. Gully was expressed by Emma, Darwin's wife: "We like Dr. Ayerst, tho' he has not the influence of Dr. Gully. Dr. G. it is hopeless to try to see tho' Imust say he has been to see Ch. (Charles) twice & he quite approves of his treatment"
Although it is not known whether it was purposeful or not, Darwin tended to seek the care of doctors who not only practiced hydrotherapy but also homeopathy. For instance, while his seminal book, The Origin of Species, was at the printing press, he was visiting Ilkley Wells, a water-cure spa operated by Dr. Edmund Smith, a homeopathic doctor.
Hydrotherapy: Darwin and Dr Lane
Darwin never returned to Malvern, but found another hydrotherapist, Dr Edward Wickstead Lane. Darwin's condition then was much as when he had first seen Gully, and Dr Lane later wrote
"I cannot recall any [case] where the pain was as poignant as his. When the worst attacks were on, he seemed crushed with agony."
Lane's regime did not include clairvoyance, mesmerism or homeopathy; as Darwin wrote, Lane did "not believe in all the rubbish which Dr G. does," and Darwin became a convert, "well convinced that the only thing for Chronic cases is the water-cure", and wrote "I really think I shall make a point of coming here for a fortnight occasionally, as the country is very pleasant for walking." He told Hooker he had
"already received an amount of good, which is quite incredible to myself & quite unaccountable.—I can walk & eat like a hearty Christian; & even my nights are good.— I cannot in the least understand how hydropathy can act as it certainly does on me. It dulls one's brain splendidly, I have not thought about a single species of any kind, since leaving home."
Hydrotherapy, as practised by Lane, Gully and many others, was a treatment for chronic illness, and was conceived as working by promoting the "Power of Nature" to effect a cure. Treatment involved withdrawal from all drugs; according to Gully, quoting John Forbes, "in a large proportion of the cases treated by allopathic physicians, the disease is cured by Nature and not by them"; that "in a lesser, but still not a small proportion, the cured by Nature in spite of them"; and that consequently, in most cases it would be better "if all remedies, especially drugs, were abandoned." Hydrotherapy involved removing all stimulants including alcohol from the diet, and required quiet rest and a degree of seclusion - the cure would not work, according to Gully, if attempted amidst the gaiety and distractions of city life. Gully asserted nothing miraculous or supernatural about the healing properties of water; for him hydrotherapy involved a clean and simple diet in restful surroundings , with frequent mineral water baths, foot baths, douches etc. - and drinking mainly water.
"Some modern medical historians with a psychoanalytic bent have found "a wealth of evidence that unmistakably points" to the idea that Darwin's illness was "a distorted expression of the aggression, hate, and resentment felt, at an unconscious level, by Darwin towards his tyrannical father". One suggests that his turning to science was mainly the consequence of "reaction to sadomasochistic fantasies concerning his own birth and his mother's death". Another explains how in dethroning his Heavenly Father Darwin found solace for being unable to slay his earthly one. Attention has further been drawn to a continuous preoccupation on the part of Darwin with matters to do with sex. Revealing himself as a master ironist, Peter Medawar remarks on this last point:"We need look no further than the titles of his books: 'The Origin' itself, of course; 'Selection in Relation to Sex'; 'The Effects of Cross- and Self-Fertilization in the Vegetable Kingdom'; and 'On the Various Contrivanoes by which Orchids are Fertilized by Insects'. With so great a load of guilt, need we wonder that at the age of 33 Darwin should have retired from public life to live in quiet seclusion in the country? It was a sacrificial gesture, even a crucifixion: and Kempf calls attention to the inner significance of the fact that it was at the age of 33 that Christ himself was crucified."
Editorial (1964) Darwin's Illness Canad Med Ass J 51:1371-2
Many books and papers have tried to explain Darwin’s illness as organic or psychosomatic or a combination of both, including arsenic poisoning; typhoid; Ménière's disease; Chagas’ disease; multiple allergy; hypochondria; panic disorder with agorophobia; repressed anger towards his father; stress; Crohn's disease; .or bereavement syndrome.
His medical history shows he had an organic problem, possibly exacerbated by depression. According to Campbell and Mathews (2005), Darwin’s symptoms match systemic lactose intolerance; in particular, vomiting and gut problems showed up two to three hours after a meal, the time it takes for lactose to reach the large intestine, and his family history shows a major inherited component, as with genetically predisposed hypolactasia. Darwin only got better when, by chance, he stopped taking milk and cream.
Chagas' disease, sometimes called "Darwin's disease", was first described by the Braziliian medical scientist Carlos Chagas Sr in 1909. The disease is an incurable parasitic illness with some similarities to AIDS. Chagas' is caused by a micro-organism Trypanosoma cruzi named in honour of another Brazilian scientist, Osvaldo Cruz, and it has no cure. Like AIDS, it damages the immune system, usually after a long delay (20 to 30 years). The most common tropical disease in Latin America, Chagas has infected 17 million people--750 times the number reported with AIDS. The huge blood-sucking bug Triatoma infestans, the benchuca, is the chief vector of the disease.
In 1959, Saul Adler first proposed that Darwin had Chagas' disease because Darwin had been attacked by T. infestans in 1835 in an area where Chagas' is endemic:
"At night I experienced an attack (for it deserves no less name) of the Benchuca a species of Reduvius, the great black bug of the Pampas. It is most disgusting to feel soft wingless insects about one inch long crawling over one's body. Before sucking, they are quite thin but afterwards they become round and bloated with blood, and in this state they are easily crushed". (Charles Darwin, March 25, 1835)
Darwin was generally vigorous before 1839, particularly so throughout the 'Beagle' voyage, and his symptoms are generally compatible with Chagas' disease. Patients with chronic Chagas' disease are very sensitive to catecholamines and exacerbations of symptoms with stress are expected. Acute onset is rare; symptoms usually occur up to several years from the initial infection.  
Against this hypothesis, Darwin lived a relatively long life, and the symptoms abated as he aged, which is not typical for the disease. Some of his symptoms, including fatigue and palpitations, were already present before the Beagle voyage; the partial exacerbations and remissions are unusual in Chagas' disease; the incidence of Trypanosome-infested benchucas in Mendoza, where Darwin reported the bite, is relatively low within the region as a whole; and no other members of the Beagle expedition succumbed to a similar disease.
- Sir George Pickering, quoted by Katz-Sidlow RJ (1998) In the Darwin family tradition: another look at Charles Darwin's ill health. J R Soc Med 91:484-8 PMID 9849520
- Darwin Correspondence Project, Letter 847 — Darwin, C. R. to Hooker, J. D., 31 Mar 1845
- Darwin Correspondence Project, Letter 1236 — Darwin, C. R. to Hooker, J. D., 28 Mar 1849.
- Gully, James Manby (1856). The water cure in chronic disease., 5th Edition. Churchill.
- Gully was a member of the British Homoeopathic Society in 1848
- Darwin Correspondence Project, Letter 1234 — Darwin, C. R. to Darwin, S. E., 19 Mar 1849
- Before the lamp bath, hydrotherapists induced perspiration in patients by the ‘blanket sweat’, in which the patient was wrapped in blankets and an eiderdown
- Darwin Correspondence Project, Letter 1235 — Darwin, C. R. to Fox, W. D., 24 Mar 1849
- Darwin Correspondence Project, Letter 1240 — Darwin, C. R. to Fox, W. D., 18 Apr 1849
- Letter 1352 — Darwin, C. R. to Fox, W. D., 4 Sept 1850
- "He was urged to try to water cure by Fox (or Sulivan) and at last agreed to try Dr. Gully's establishment.1 — His letters to Fox show how much good the treatment did him: I fancy he thought that he found a cure for his troubles, which but like all other remedies it had only a transient effect on him. However he found it at first so good for him that he built himself a douche when he came home, & Parslow learned to be his bathman. He thought Dr. Gully a clever Dr but I do not think he liked him. He was repelled by all the homeopathy & spiritualism that Dr Gully favoured. — He so far humoured Dr G. as to allow himself to be examined by a medical clairvoyant who localized the mischief in the stomach, in doing so he followed as my father believed some unconscious hints from Gully or his assistant." Memoirs of Charles Darwin's son, Francis The Charles Darwin Library online
- in Burkhardt, 1985, XI, p. 643, September 29, 1863.
- Burkhardt, 1985, XI, p. 361.
- Peter Medawar is quoted from his chapter "Darwin's Illness" in The Strange Case of the Spotted Mice Oxford University Press
- Seereviewby WD Foster in Isis(1972) pp 591-2 of John H Winslow's 1971 book Darwin's Victorian Malady...
- Barloon TJ, Noyes R (1997) Charles Darwin and panic disorder JAMA 277:
- Pasnau RO (1990) Darwin's illness: a biopsychosocial perspective Psychosomatics 1990; 31:121-128
- Paul Martin The sickening mind: brain, behaviour, immunity and disease. Harper Collins ISBN 0002556839, reviewed by Richard Mayou in Darwin's dual disease for Times Higher Education
- Orrego F, Quintana C (2007) Darwin's illness: a final diagnosis.Notes Rec R Soc Lond 61:23-9. "We have concluded that he suffered from Crohn's disease, located mainly in his upper small intestine. This explains his upper abdominal pain, his flatulence and vomiting, as well as his articular and neurological symptoms, his 'extreme fatigue', low fever and especially the chronic, relapsing course of his illness that evolved in bouts, did not affect his life expectancy and decreased with old age, and also the time of life at which it started. It apparently does not explain, however, many of his cutaneous symptoms." See also Sheehan W et al. (2008) More on Darwin's illness: comment on the final diagnosis of Charles Darwin. Notes Rec R Soc Lond 62:205-9. PMID 19069001
- Campbell AK, Matthews SB (2005)Darwin’s illness revealed Postgrad Med J 81:248-51
- Darwin's Disease Economist (05/05/90) 315:105
- Adler S (1959) Darwin's illness. Nature184:1102-4. PMID 13791916
- Adler S (1965) Darwin's illness Br Med J 1(5444):1249-50. PMID 14275525
- Chagas Disease Claimed an Eminent Victim. The New York Times, June 15, 1989.
- Bernstein RE (1984) Darwin's disease: Chagas disease resurges J R Soc Med [http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1439957&blobtype=pdf 77:608-