LICHEN (lichen Tuber), in medical terminology, a papular disease of the skin, consisting of an eruption in small thickly set, slightly elevated red points, more or less widely distributed over the body, and accompanied by slight febrile symptoms.
Its use in febrile diseases, at one time extensive, is now obsolete.
The labours of Golgi, Marchiafava, Celli and others established the nature of the parasite and its behaviour in the blood; they proved the fact, guessed by Rasori so far back as 1846, that the periodical febrile paroxysm corresponds with the development of the organisms; and they showed that the different forms of malarial fever have their distinct parasites, and consequently fall into distinct groups,.
Salicylates are the next safest to quinine of all antipyretics, whilst being much more powerful in all febrile states except malaria.
By his almost exhaustive comparison of febrile movements as symptomatic processes Wunderlich dealt the last blow to the expiring doctrine of the "entity" of "fever"; while on the clinical side Bretonneau and Louis, in 1862-1872, by their careful clinical and pathological studies of forms of fever, relieved the new doctrine of the extravagances of Broussais, and prepared the way for the important distinction of enteric from typhus fever by A.