This section is from the book "The Home Hand-Book of Domestic Hygiene and Rational Medicine. Volume 2.", by J. H. Kellogg, M.D.. Also available from Amazon: The Home Hand-Book of Domestic Hygiene and Rational Medicine, Volume 2.
Usually begins with weakness, coated tongue, diarrhea, alternating with constipation, general debility, and sleeplessness; sometimes begins suddenly; tickling in the nose; coryza; prolonged and violent sneezing; swelling and redness of the eye% with evidences of acute mucous inflammation; tickling in the throat with dryness or slight burning; sometimes slight deafness; bronchial catarrh; great difficulty in breathing, with tightness about the chest and croupy symptoms; attacks most frequent in daytime, instead of night as in nervous asthma; sometimes frequent chills followed by considerable fever.
This curious disease has been very closely studied for a number of years, and yet its cause is, at the present date, still undetermined. It has been believed by many eminent physicians that the disease is caused by the pollen of plants or grasses, and experiments conducted by an eminent German physician seem to confirm this view; but it has not been determined what particular plants furnish the noxious pollen. Attention has been specially called to the rag-weed, a very common plant almost everywhere, as it has been observed that the occurrence of the disease in a large number of persons is simultaneous with the flowering of this plant. We have frequently been told by patients that they believed this to be the cause of the disease in their particular cases at least. On the other hand, there are those who hold the disease to be chiefly a nervous disorder. Our friend, Dr. Geo. M. Beard of New York, has collated a large number of facts upon this subject which seem to show beyond any room for doubt that one of the essential causes of the disease is individual idiosyncrasy. The exciting cause is probably different in individual cases, which accounts for the fact that different persons are affected at different seasons of the year. The disease usually lasts four to six weeks, and leaves the patient almost as suddenly as it appears, in some instances observing in its departure the very same regularity, even to the hour, as is observed in some cases in its commencement. The disease is rarely or never fatal, but usually leaves the patient weak and debilitated.