DIGITALIS, the purple foxglove, has been for the past 175 years the most valuable drug in the possession of the physician for use in the treatment of heart disease. It came into use as a heart remedy in 1776 when Wm. Withering learned of its efficacy in the treatment of dropsy from the “Old Woman of Shropshire.”.
In 1785 he published his memorable treatise, “Account of the Fox Glove,” wherein he warned against the misuse of the drug, which was becoming evident at that early date of medical practice.
Burt, in his Materia Medica, says : “Through the cerebro- spinal system, digitalis has eleven special centers of action. Heart, Arteries, Vagi, Kidneys, Stomach and Colon, Liver, Sex Organs, Brain, Eyes, Cord and Temperature. The great central action of this remedy is upon the heart and arteries.”.
Dr. Willius of the Mayo Clinic says : “In spite of the many actions that have been ascribed to digitalis from time to time, the practical facts regarding its known effects on the diseased heart of man may be summarized briefly. In therapeutic doses digitalis has been known to increase the amplitude of ventricular contractions by its direct action on the cardiac muscle. Slowing of the heart occurs under certain conditions, particularly in auricular fibrillation, and conspicuously when the ventricular rate is rapid.
Slowing occurs from stimulation of the vagus center in the medulla, from stimulation of the cardiac vagal endings, and from direct depressant action on the auriculo- ventricular conducting system. Slowing to some degree occurs when cardiac action is rhythmic, but usually not to the same degree as occurs when auricular fibrillation is present. The actions thus briefly stated summarize the actual facts. Other effects are either speculative or occur secondarily to improvement in cardiac function.”.
Blackwood says : “This agent in small doses causes the pulse to beat stronger, firmer and slower: as a result of this the arterial tension is increased, which is due to the contraction of the muscular walls of the arteries. Large doses act as an irritant to the gastro-intestinal tract, and induce nausea, vomiting and diarrhoea. The arterial tension is greatly increased while the pulse becomes markedly accelerated.
Toxic doses produce a very rapid, irregular, soft, compressible pulse. The arterial tension is now lowered. Under these doses the respirations are slowed. The urine is increased, and with exception of urea and uric acid, the excretion of the solids is greatly augmented. Toxic symptoms are the result of its prolonged administration and its accumulative effect.”.
Bartlett has the best summing up of the uses of digitalis which I have been able to find. He says : “Digitalis has been studied carefully by physicians and physiologists for 100 years, and after such a long period it cannot be said that any definite conclusion has been reached, other than that it is a remedy of great value. It is not surprising, therefore, to note the wide discrepancies in opinions as to dosage, preparation, and the particular cases to which it is adapted. All are agreed that in auricular fibrillation it is the remedy par excellence.
In endeavoring to bring order out of all of this therapeutic chaos, let us dissect some details. First as to the dosage. There is no drug that is capable in the same dosage of producing identical effects in all individuals; in other words, all persons do not respond in the same way to the dose and the drug. We must prescribe entirely to secure the therapeutic effect, and the minimum dose to produce that effect, is the one we must use.
“In the treatment of auricular fibrillation, Eggleston and his followers have pleaded for enormous doses of digitalis to start with : say 75 to 100 minims at one dose, and then rest to observe the result. Observing the result is the rational part of the practice: the giving of the large initial dose appears to be irrational when physicians have been securing good result from much smaller amounts.
The idea seems to be to saturate the patient with digitalis at once: and then continue the drug at the rate of say 25 minims daily to compensate for any that may be eliminated. This practice is mentioned here to be condemned except in certain rare instances where the smaller dosage has failed. As a method of choice it has no place. The ordinary dosage as practiced by physicians generally, appears to be 5 minims of a standardized tincture 4 times daily. This dose, on the other hand, is too small when there is any real work to be done.
Very few cases with broken compensation do well under 40 minims daily. We are speaking now of digitalis in its undisputed sphere, viz.; auricular fibrillation. The digitalis may be continued daily in moderate dosage for an indefinite period. I have kept patients on it on doses of 15 minims twice weekly for some years, and with good effects. In mitral regurgitation, digitalis is almost as efficient as it is in fibrillation. In mitral stenosis digitalis is useless until dyspnoea appears. In aortic regurgitation there appears to be no reason why digitalis should be prescribed.
“The principal form of digitalis now in use is the tincture of which many excellent standardized preparations are on the market. There is no longer any advantage in selecting fluid extracts, far free tinctures, powdered leaves or alkaloids.”.
Dr. Arthur Gordon said that there was no better preparation of digitalis than a good reliable tincture.
Quoting again from Dr. Willius : “The tendency exists to administer digitalis on the mere mention of heart disease, when heart disease is but a suspicion, when the heart is normal, and in heart disease regardless of type of lesion or state of function. Such usage is a blatant admission of total lack of understanding of the actions of the drug and of heart disease. It is needless to say that the physician has no moral right to administer a drug unless he is fully cognizant of its actions and the hazards that may accompany its use.
The establishment of the diagnosis of heart disease frequently is considered the indication for administration of digitalis. Such a criterion is absolutely fallacious and without grounds. No method of treatment is attended by greater hazards than the indiscriminate administration of digitalis. When the physician recalls the known actions of digitalis and uses it accordingly, when its indication is clearly demonstrated, then and only then, will he prescribe it properly.”.
Digitalis in large doses, or in long-continued small doses, produces irregular heart action. Given in excessively large doses it produces symptoms which closely simulate auricular fibrillation. Physicians of all schools of practice unite in saying that in cases of auricular fibrillation, digitalis is the remedy par excellence.
To my way of thinking, the beneficial results in these cases are due to the fact that the remedy is acting according to the law of similars: that it is homoeopathic to the case.
Bartlett says : “As to the homoeopathicity of digitalis in heart diseases, differences of opinion will always prevail, each one deciding the question according to his preconceptions. Certain it is that digitalis is capable of producing all types of disturbance in the cardiac rhythm, and equally certain that it may be administered with good results in all of them, though giving much better results in auricular fibrillation than in any other. “Years before Mackenzie published his memorable studies.
Lilienthal stated that the more highly irregular the heart action, the better was digitalis indicated,and the more certain were good results to follow. Explanations presented have changed from time to time. If the drug produces, a symptomatic similarity, it becomes homoeopathic : the underlying explanation which provides for a therapeutic antagonism has no bearing on the proposition, because it is inconceivable that a cure can be effected without such antagonism. Fifty years ago, Farrington taught his students that while drugs were selected on the basis of Similia applied to symptoms and clinical phenomena, the cure itself was effected by antagonism.”.
In my own experience when I have prescribed digitalis for rapid heart action which was regular in rhythm, I got no beneficial action, but where the heart beat was irregular, the results were usually beneficial.
At various times I have been called to attend a patient who was in a serious condition from auricular fibrillation, and in such cases I have frequently administered hypodermically 1 cc. of a reliable preparation of digitalis with really wonderfully fine results. In cases where digitalis is the indicated remedy, select the proper dosage and continue its administration for a long time in this proper, safe dosage, but do not digitalize your patient.
For some years it has been the popular procedure in many of our great clinics to put the patient to bed and fill him as full of digitalis as possible without producing an immediate lethal result. This is done in cases where digitalis is not the indicated remedy, and in cases where there is no organic heart disease. You may be sure that the patient will have heart disease when he comes home and will never fully recover. I make this statement after many years of close observation of many cases who have undergone such mistreatment.
