SYRUP OF HYDRIODIC ACID. HOW AND WHEN TO USE IT.

BY HENRY M. FIELD, M. D., Professor of Therapeutics, Dartmouth Medical College, etc.

HYDE

YDRIODIC ACID is a compound which in chemical symbol is indicated by the formula, HI and in chemical composition consists almost entirely of iodine. This paradox of constitution, pertains to the fact that the equivalent of iodine is 127, the equivalent of hydrogen less than 1; hence a little over 99 p. c. of Hydriodic Acid is iodine. The syrup of this acid, the only pharmaceutical form in which it is used, was somewhat in use prior to 1870; but in that year was stricken from the U. $. P. on account of the uneven and imperfect methods by which it was prepared, and also its frequent instability. For several years thereafter it remained unemployed and indeed, had become nearly obsolete, when through the successful efforts of a New York chemist, it was reïntroduced to the medical profession being thus received into the general favor which it has since enjoyed. And, indeed, it was no small service which R. W. Gardner thereby rendered to practical therapeutics; the Syrup of Hydriodic Acid as prepared by his method, and restored to pharmacy by his enterprise, has held its ground ever since such introduction, being of uniform strength,

the necessary conditions of its preservation are met, and of agreeable taste.

The original gift and service of Mr. Gardner should always be kept in mind and receive due and grateful recognition on all proper occasions. No less than this the writer feels bound to say; and to add that there must be many physicians and druggists through the country who, like himself, will always hold in pleasantmemory an interview or communication of years ago, in which the information sought was freely and effectively afforded; and this in a way, also, which bespoke the gentleman as well as practical scientist.

A magistral Syrup of Hydriodic Acid is estimated to represent 6 gr. of iodine in each ounce, is of the consistency of lemon syrup, of agreeable sub-acid taste, of pale straw color and must be absolutely free from insoluble particles. Moreover, it may be regarded a stable compound, so long as essential conditions, both as to its keeping and use, are intelligently observed. It must not be exposed to a strong light, or left long exposed to the air; avoidance of either extreme of temperature is equally imperative. Approach either to 32° or 100° Fahr. not alone endangers the loss of medicinal properties but also makes liable a change in chemical constitution, through which a positively deleterious action may result.

As already said, a good specimen of the Syrup will be of a fixed, uniform

color and will present translucency,-be absolutely free from insoluble particles, —and this, whether held in suspension or precipitated. A faulty preparation, -faulty at first because not made right, or afterwards because not kept as it should be,—will most often present departure from the standard in two corresponding particulars: will be red dish or reddish-brown in color, and to use a common word, will be turbid. Such specimen cannot fail alone to exert the properties for which the remedy is prescribed; there is danger lest it further exert the properties of an. irritant and toxic. A syrup presenting signs of reddish color and turbidity, also presents evidence of chemical decomposition, and among the products of decomposition, iodine in precipitated form.

THE DISPENSING, CARE AND PRESERVATION, INGESTION, ETC. OF HYDRIODIC ACID.

However it may be with his usual prescriptions, the physician should always give attention to the source from which this remedy is procured. It may be just that pharmacist, who has not the skill to make the preparation himself, who will often prove ignorant or indifferent as to the honesty or skill of the manufacturer from whom he buys.

Again, should the essential, initial care have been properly exercised, it is equally imperative that, the medicine once procured, a complete and intelligent understanding should exist between physician and patient, as to the treatment it shall receive, while in the hands of the latter, with purpose to ensure its continued integrity. A lack of proper attention given to the points thus made, (and to another soon to be presented, and which, if possible, is of greater moment), is chiefly responsible for partial result, positive failure, in the use of the Syrup, and, too often, for unmistakable injury attending upon its use.

The ingestion of the remedy demands the strict attention of the prescriber; and in this particular, with the many

results involved, the latter is alone responsible as, upon details just presented, he shares responsibility, in varying degree, with the druggist. But, above all, it is a determination of the hour with reference to eating, when the medicine shall be taken, which is of importance, of capital importance; and, still here again, error, ignorance, indifference will not alone bring failure in medication but, often, deleterious results also.

Now unless the writer is strangely misinformed, the standard books and teachers seldom give emphasis to this capital condition, as we conceive it to be, in the use of the remedy; too often, pass it by without notice. Many medicines can afford such slight and dismissial; Syrup of Hydriodic Acid cannot afford it. In all that directly concerns the ingestion of this remedy, there must be consciencious instruction on the part of physician, intelligent coöperation between the physician and patient, strict obedience of the latter to the former, or the medicine had much better never been prescribed.

Just here, and as pertinent to the immediate subject, a somewhat personal remark may be excused; first, in the writer's capacity as writer, again in his capacity as practitioner. As said heretofore, if he is informed upon the subject of present consideration, if his estimate cf a material which has been an object of use, study and instruction on his part for many years, is correct, we have now reached that stage of the discussion which, with purpose of all possible brevity, demands in its treatment, a concession of whatever space may be required, even, although as compensation, some other departments are passed rapidly and curtly in review.

Again, as practitioner, he is free to confess that, in early experience with the remedy, it was prescribed for some time and with repetitions before it began to be realized that there had been wrong. misconception, neglect upon a condition more essential to the success