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

by Andrew Duncan

This form may, upon the whole, be esteemed, although not a powerful, yet, in many cases, an useful preparation. It is chiefly preferable to other mercurials in those recent cases of lues venerea where a weak preparation will answer the purpose; and where, at the same time, it seems most adviseable that the mercury should be slowly introduced into the system.

The three preparations of mercury which have already been treated of, when compared with many others, may be esteemed mild. There are a different set, which, in opposition to these, may be termed acrid. Of the acrid preparations, not a few have likewise been used in the cure of lues venerea, and for this purpose introduced into the system in different forms. To treat of all of these would not only be deviating from our first intended plan, but would lead to many unnecessary repetitions, and needless inquiries, with regard to medicines which are now by no means in common use. Calomel and corrosive sublimate may be esteemed the two extremes of the acrid preparations; the first being the mildest, the last the most stimulant, which is, in the present practice, ever used internally. These two are, at the same time, the acrid preparations which are perhaps most frequently employed in the cure of lues venerea. To treat of these therefore will be sufficient.

Calomel, it has been observed, may be considered as the mildest of the saline preparations of mercury. In this preparation, the basis of which is the corrosive sublimate, the mercury is reduced to the form of a saline compound, by means of the muriatic acid. But it is afterwards rendered less acrid, from the addition of fresh mercury in repeated sublimations. It has by many been esteemed the most useful of the mercurial preparations, not less for other purposes for which mercury may be employed than for the cure of the venereal disease. The good effects which may be obtained from its use in this complaint are confirmed by undoubted experience. And, when it is introduced into the system, there can be no question with regard to its efficacy in destroying the venereal virus.

Calomel acts as a more general stimulant in the system than the milder preparations of mercury. And it discharges itself by the different excretories, when present in the mass of circulating fluids, in no very considerable quantity. Hence, it can be less accumulated in the system than the other preparations formerly mentioned. To this circumstance it is probably owing, that it less frequently excites salivation than these do. If, indeed, it be given in large doses frequently repeated, and does not at the same time affect the intestinal canal, it will excite salivation. From this, it may be concluded, that then the active mercury is present in the system in a very considerable quantity. But, when in this way, even such an accumulation can be obtained, it is to be considered only as on the same footing with the milder mercurial preparations, in those constitutions which are readily salivated. Here, therefore, as in habits naturally disposed to salivation, the presence of any quantity of mercury in the system will be very transient, and a salivation occurring will often frustrate the cure to be expected from it.

Calomel, from its general stimulant power, may readily be supposed to affect the intestines more considerably than the milder mercurial preparations; and, in fact, it is found, that, in many cases, it much more readily excites looseness than they do. From this circumstance, it can be less easily introduced into the system, especially if the alimentary canal possess uncommon irritability.

If these assertions with regard to this mercurial preparation be well founded, it will be easy to determine in what cases calomel is preferable to other mercurials, and in what it is to be considered as less proper. It cannot be considered as well adapted for those inveterate and obstinate cases in which a long and gradual use of mercury is requisite, and to overcome which it is necessary that a considerable quantity of mercury should be accumulated in the circulating system. On the other hand, if the intestines are not very irritable, it will be particularly serviceable, in many recent cases, in which a speedy action of mercury is adviseable; and, in those where the venereal virus has not yet made its way into the circulating system, but is detained in the lymphatic, or in the mucous glands. From its sudden evacuant power, it may likewise be of great service where mercurials in the venereal disease are intended to be conjoined with an antiphlogistic course, or to make a part of it.

What has been said of calomel may be considered as sufficient, with regard to the milder part of the saline preparations. It now only remains, then, that some observations should be offered on corrosive sublimate, which is the most acrid of these that is usually employed internally.

Corrosive sublimate, it has already been observed, is the basis of the preparation last treated of. But, in this preparation, the mercury, from the proportion of muriatic acid which is united with it, is in a very acrid state. When taken in substance, even in a very inconsiderable quantity, it proves a virulent poison to the human frame. To this circumstance it was probably owing, that, for a very long time, it was used only for external purposes, and even then, from its high stimulant power, not without the greatest caution. But the many inconveniencies attending salivation, which was at the same time found to be by no means absolutely necessary to a cure, induced practitioners to make trial of preparations less apt to have that effect, than those which had formerly been used. As every preparation of mercury, in proportion to its acrimony, has a greater tendency to act upon the surface, and less to affect the salivary glands, it is not surprising that corrosive sublimate should at length have been proposed.

The violence with which corrosive sublimate acts, has always been a sufficient reason to prevent its being thrown in, either in large quantities, or in substance. Of late years, however, a weak solution in ardent spirits has been recommended as an efficacious remedy, and often used with success. But, as it has been found that the mercury is apt to precipitate from this menstruum, if the solution is kept for any time, water has often been substituted to the spirits. Water is perhaps, in every case, even by itself, a better menstruum than spirits; but, besides this, it may be much improved, from having its solvent power increased by the addition of sal ammoniac. By this means, the precipitation of the mercury may be, in a great measure, if not totally, prevented.

Corrosive sublimate, when introduced into the system, is, as well as calomel, very universally stimulant. But its chief tendency, unless prevented by some accident, is to operate upon the surface. For the most part, it powerfully excites diaphoresis, and in this way is speedily evacuated from the system. But, if there is in the patient’s constitution a want of disposition to diaphoresis, or if the discharge by the surface is suddenly checked by the application of cold, it frequently acts upon the salivary glands, inducing salivation.