Observations on the Operation and Use of Mercury in the Venereal Disease

by Andrew Duncan

But, it may further be objected to this mode of employing mercury, that the quantity of active mercury, which in this way is introduced into the system, cannot be easily ascertained. And that, even before any obvious effect is produced, a much greater quantity may be thrown in, than is really necessary for a cure, from which troublesome consequences will afterwards ensue. These indeed are facts which cannot be denied; and it must even farther be allowed, that all the good effects in the cure of lues venerea, which can be obtained from this method of introducing mercury into the system, may be had from the internal use of other preparations equally mild, and from which the patient is not exposed to the same inconveniences.

From these circumstances, it may be concluded, that the introduction of mercury into the system in the way of unction, is neither proper in slight cases, nor in the greatest number of obstinate ones. There are, however, constitutions in which mercury, in any form, is very apt to produce an immediate and violent action upon the alimentary canal. Sometimes it excites vomiting, but more frequently it induces looseness. In such constitutions, these effects do indeed often follow, even when the mercury is introduced by the absorbents on the skin. But they are more certainly the consequence of the immediate application of mercury to the alimentary canal itself. Besides this, when these effects happen from the immediate application of mercury to the alimentary canal, the introduction of the medicine into the system, is often in a great measure, if not entirely, frustrated. And farther, the effects of mercury on the alimentary canal not only less certainly follows, from its introduction by the surface, than from immediate application, but may likewise be more easily obviated. In such circumstances, therefore, a cure of venereal complaints may, with greater certainty and ease, be affected, from the introduction of mercury by the surface in the form of unction than from any other mode of using it.

Perhaps the most common form of exhibiting mercury in this place, with a view of entering the system, is that of the mercurial pills. These, when properly prepared, seem, in most cases, to be justly entitled to the preference, which is here so frequently given them. The mercury, in this preparation, is rendered active by the same means, and is in the same state as in the preceeding one. Its operation likewise in this form is very analogous to what it is in the one formerly mentioned. It is here equally apt to salivate as in the form of unction. But the salivation induced by the mercurial pills very rarely arises to so high a degree, at least so suddenly, as from unction. The quantity of mercury introduced into the system in this form, admits of being more certainly ascertained than by unction. The principal ambiguity which takes place with regard to the pills, arises from the difference of care with which they are prepared, and the degree of solubility in the stomach which those substances possess with which the mercury is combined.

The mercurial pills affect the guts less than many other preparations of this metal. This indeed might be inferred from considering that the mercury is here in a very mild state.

From the use of mercurial pills, mercury may be introduced into the system in very considerable quantities. But, as in this form it is not readily discharged by the different emunctories, it is apt to be accumulated in a greater quantity than is requisite for slight cases. In these, therefore, the pills are not so advisable as some other preparations. But, where the alimentary canal can bear mercury with ease, the mercurial pills are perhaps preferable to any other form, for those obstinate cases where it is requisite, that a considerable quantity of the medicine in an active state should be introduced into the system. And they are particularly proper in those cases which are only to be overcome by a gradual and long continued use of mercury.

To the forms of exhibiting mercury which have already been mentioned, those lately introduced by Mr Plenck of Vienna may properly be subjoined. Of the various preparations which he has proposed, what he seems chiefly to have used himself, and what has been principally employed here, is his simple mercurial solution. What is to be said, then, concerning his preparations, as they are all very similar in their nature, may be confined to this form.

This gummous solution is, in the table of mercurials, reduced to the same general head with the two preparations last treated of; the mercury in this case likewise being rendered active by division from triture. Although the use of this preparation is but a late proposal, yet, since its introduction, it has been a good deal employed, and the facts which may be had with regard to it cannot be alledged to be few. That general observations, however, may, with justice, be made, numerous facts are requisite; and perhaps what can as yet be had on this subject are still an insufficient foundation for any certain conclusions.

It may, however, with regard to this medicine, be confidently asserted, that the opinions upon which its superior efficacy is founded are without foundation. It is a mistake to suppose, that any peculiar affinity, or specific elective attraction, takes place betwixt mercury and vegetable mucilage. And mercury with gum, as well as in other forms, if, from triture, it be rendered sufficiently active, and if it be introduced into the system in sufficient quantity, will also excite salivation. This preparation, then, is still to be considered as, in a great measure, on the same footing with the two others already mentioned.

But, united with vegetable mucilage, mercury seems to act less upon the intestines than the mercurial pill. This is probably to be referred to the viscidity of the substance with which the mercury is here combined. Vegetable gum possesses a remarkable power of sheathing and defending those parts to which it is applied against acrimony of any kind.

This preparation, taken in what would seem an equal proportion with the mercurial pill, shows a less powerful action on the system, both in its effects on the excretions, and in its influence on the morbid symptoms. This diminution of action may perhaps, in some degree, be accounted for from the mercury being less readily absorbed into the system, after entering the alimentary canal, in consequence of the viscidity of the gum with which it is united. But as vegetable mucilage, when taken by itself, is observed to diminish the action of mercury, in whatever way it be introduced into the system, this effect must be principally accounted for from some other cause. Probably it depends upon the influence of the mucilage, after having entered the system, in defending the excretories against the violence of the stimulus from the mercury.