This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
Nitromuriatic acid promotes the appetite, and in other respects operates as a tonic to the digestive function, in the same manner as nitric acid. Like that acid, too, it is irritant to the alimentary mucous membrane in over-doses; and, when swallowed in great excess, or in a concentrated state, acts as a corrosive poison, with the same phenomena as those already described as the result of poisoning by the mineral acids. The antidotes and remedies are also the same. (See pages 357-8).
But this medicine produces other and very important effects upon the system. It is certainly not absorbed precisely as administered; for the nitric acid, which, as before stated, is contained in it in excess, probably never enters the circulation unchanged. There can hardly, however, be a doubt that one or more of the new bodies, resulting from the reaction of the ingredients, is really absorbed. This can scarcely be the chlorine; for the chemical affinities of that element are so powerful, that it could not remain long enough in the primae viae, or in contact with the tissues through which it must pass, without satisfying those affinities by union with some other body elementary or compound. May it not be, that the new compound noticed by M. Baudrimont, or one or both of those which offered themselves to Gay-Lussac's research, are capable of absorption, and of producing all the peculiar effects of the medicine upon the blood, and upon the tissues to which they are conveyed by the blood?
An evidence of this action through the circulation is presented in the increased secretion of bile, causing not infrequently bilious evacuations from the bowels, and in the fact that this occurrence takes place as well from the external as from the internal use of the medicine, proving that it is not merely an irritation propagated from the intestinal mucous membrane through the gall-ducts to the liver. Another evidence of the same kind is the occasional salivation and sore mouth which follow the use of the medicine, whether swallowed or applied to the skin; effects, to the reality of which, though they are by no means constant, I can myself bear witness. Further proofs are offered by the therapeutic influence of the medicine in correcting fetid breath, and modifying the urinary secretion so as to prevent the elimination of oxalate of lime. It probably acts, in both of these instances, by decomposing and destroying substances in the blood which cause these morbid phenomena, while it leaves the normal constitution of that fluid unaffected.
It is in vain to speculate upon the precise method in which these purifying effects are produced. We have not yet light enough to justify even an attempt to form an explanatory theory on the subject; though we may reasonably appeal to facts for proof of the reality of the effects referred to.