The Dual Action of Drugs.
Editor Ellingwood's Therapeutist;
I have your favor of the 20th instant and am pleased to have attracted the attention of a therapeutist of your calibre. At the same time I regret that you maintain the theory of the dual action of drugs, that which I regard as the source of a constant misunderstanding concerning drug action.
No one claims a dual action for veratrum viride because it is a depressant and its minute dose is always useless or worse. I am at loss to understand why aconite and other stimulants should be credited with a dual action; how they can be stimulants one moment, and depressants the next. If they are stimulants at any time they are always stimulants, just as a depressant is always a depressant, and the results of their administration, that are said to be due to their depressing action, are due to over stimulation inducing less or more paralysis.
I would be as much justified in claiming a triple action for ipecac, which is always a stimulant, for in vomiting, when depressed vitality is present, small doses cure promptly, and the less the depression, the more the minute dose is the efficient dose.
Increase the dose enough, and vomiting is always induced through its stimulant, or so called irritant effect, but a larger dose is demanded for this effect when the vital energy is depressed than when it is not.
Increase the dose to the enormous quantities given for dysentery and they become curative in that case by giving rest by over stimulation, inducing paralysis of intestinal sensation or motion. The dual effects of alcohol, strychnine, etc., can be, I believe, explained upon the same principle.
In my opinion the dual action of drugs is a myth. Homeopathy's drug in minute doses succeeds only when the patient is depressed, and the drug is a stimulant. For instance, Hughes in his pharmacodynamics gives ten times as many pages to aconite as to veratrum, and the thirtieth dilution of the former is prescribed, while the smallest dose of the latter he suggests is the first dilution. Holding the foregoing views the reason is obvious, and once generally grasped, the profession will "see a great light," therapeutically.
I believe you are doing a great work in hastening therapeutic reform, and trust you will regard this as a sincere effort to add my mite to the good work, and will believe me, Yours faithfully,
GEO. M. AYLESWORTH, M. D., Collingwood, Canada.
COMMENT: The above letter was not written for publication, but with the doctor's subsequent consent, I publish it with great pleasure, because it brings out a reasonable theory, a rational idea, concerning the so-called dual action of drugs. I am constantly on the look-out for just such theories as the above. It is the presentation of these, and their thoughtful consideration by our readers that will enable us ultimately to arrive at approximately correct conclusions, concerning drug action. At first thought I was not inclined to accept the doctor's opinion, but I have since kept my mind on the idea as he has presented it, and I believe that I can now. see very good reasons why his statement is applicable to at least several of our remedies.
We have claimed dual action for bryonia. This remedy produces the best results in small doses. We have no way of knowing that its violent, irritating and depressing effects in large doses are anything else than an intensification, an exaggeration of this same satisfactory influence, exercised to too great a degree. I shall certainly keep this idea of the doctor's in mind in my future study of some of these drugs, and shall be glad to hear an expression from others on these lines.