Serum sickness proteins to form immune complexes. These complexes precipitate, enter the walls of blood vessels, and activate the complement cascade, initiating an inflammatory response and consuming much of the available complement component 3 (C3). The result is a leukocytoclastic vasculitis. This results in hypocomplementemia, a low C3 level in serum. They can also cause more reactions resulting in typical symptoms of serum sickness. Serum sickness can be developed as a result of exposure to antibodies derived from animals. These sera or antitoxins are generally administered to prevent or treat an infection or envenomation. Some of the drugs associated with serum sickness
Blood, toil, tears, and sweat are "It [poetry] is forged slowly and painfully, link by link, with blood and sweat and tears" (Lord Alfred Douglas, 1919), "Blood, sweat, and tear-wrung millions" (Lord Byron, 1823), and "...mollifie/ It with thy teares, or sweat, or blood" (John Donne, 1611). In Latin, Cicero and Livy had used the phrase "sweat and blood". "We are in the preliminary stage of one of the greatest battles in history... That we are in action at many points—in Norway and in Holland—, that we have to be prepared in the Mediterranean. That the air battle is continuous, and that many preparations have