Dr. Rees and others have found Lemon juice of great use in the treatment of acute Rheumatism. It contains Citric acid, and some Citrate of Potash; the latter being in too small amount to explain the action of the remedy. I have already shown how it seems possible that the vegetable acids may act as refrigerants in simple fever; how they may then supply the place of the natural lactic acid in the blood, and become oxidized instead of the Proteinaceous compounds. (_Vide Acids._) But Rheumatic fever is a very different case, for there is here apparently an excess of lactic acid, and an arrest of its oxidation. In considering, however, the formula for Citric acid, we perceive that not only does it contain proportionally more Oxygen than Proteins, as was proved in the former instance, but more than lactic acid contains. It is
Thus it is possible that it may act as a carrier of oxygen to the lactic acid, and so help it on towards its transformation into carbonic acid. It appears to be decomposed in the system, for Dr. Rees has never known it in these cases to increase the acidity of the urine. The matter is obscure; but we can discern enough of it to convince us of the possibility of different medicines acting in diverse ways so as to produce very similar results.
Colchicum has apparently some power in the diversion or control of these morbid processes, which we can only indicate, but cannot further comprehend. It is generally best to give it so that it shall neither produce purging, nor any great degree of general depression.
Mercury and other medicines which promote the secretion of the liver, are found to be of considerable use in the treatment of all of these diseases, but more especially in Gout. They seem to act by virtue of their power in eliminating and producing Bile. And it is likely that some constituent of Bile, reabsorbed into the blood, is able to exert a beneficial influence on the conduct of such processes as those which we have just now considered.
Quinine and Tonics have been strongly recommended by Dr. Todd in Gout; and they seem to be signally efficacious, both in this and in the other Arthritic disorders. This is a very interesting fact. If there should be any truth in an idea which I have explained at length in the article on Tonics (_vide_ p. 142,) it would seem that these Tonics may be of use by supplying in the blood the place of one of the wanting elements of Bile. For in all Arthritic disorders there is more or less of hepatic derangement.