HOMEOPATHY. - From ὅμοιος = similar, πάθος = suffering: a therapeutic system founded on the law of similars (similia similibus curantur), conceived by Hippocrates, confirmed by Paracelsus, definitively enunciated and developed by Samuel Christian Frederick Hahnemann (b. 1755, d. 1843), doctor of medicine of the University of Erlangen (Germany).
To dispel whatever may appear paradoxical in the concept — that diseases are cured by means of similar diseases — there stand numerous clinical observations of cures that occurred upon the supervening, in one and the same patient, of a morbid affection very similar to the one already present. But the best commentary on the law of similars lies in the constitutional and synthetic conception of disease which Hippocrates was the first to hold, which Hahnemann placed at the foundation of homeopathy, and which modern clinical medicine has taken up again, updated and developed through the work of A. De Giovanni, G. Viola, N. Pende, in Italy, and abroad especially of the Frenchman L. Lévy and the Spaniard G. Marañon. The Hippocratic idea appeals above all to the general and constitutional causes of diseases; without denying the importance of external morbific agents, it seeks above all to recognize the characteristics of the morbid "soil"; and it considers the patient's symptoms not as harmful annoyances that the physician must in any case remove, but as the genuine expression of a natural defense of the organism. It follows that a rational therapy will not be directed at combating, but in a certain sense at favoring and strengthening the patient's symptoms in order to aid the effort of healing nature.
It is to Hahnemann's credit that he intuited that drugs can be usefully prescribed according to this criterion and employed in such a way as to reproduce in each patient a symptomatic picture, a small artificial disease which, by superimposing its own symptoms on the natural ones by virtue of a perfect similarity, intensifies them just enough to maximize the salutary reaction.
Cases of morbid affections whose cure could not be explained without the intervention of the law of similars, perhaps unknowingly applied, are quite frequent and were known to clinicians even before homeopathy. Thus, for example: the observations of Muralto and Wedel on the beneficial action, in certain colics of children, of jalap, which in current dosage produces colics and intestinal discharges in healthy subjects; the cure of certain conjunctivitides by means of euphrasia, which at normal doses tends to inflame the mucosa of the eye (Murray); the hemorrhages that Baglivi, Barbeyrac and Dalberg saw cease under the action of ipecacuanha, a remedy notoriously capable, at determined doses, of producing hemorrhagic states; the treatment of seasickness with tobacco, which in turn can provoke characteristic syndromes of nausea and violent vertigo; the beneficial results observed by Whistling in certain varieties of epilepsy with the use of agaricus muscarius, which, in cases of poisoning, essentially provokes tremors, convulsions and loss of consciousness, in a picture most closely resembling that of an epileptic attack. In all these cases there appears the beneficial intervention of a disease artificially produced by the "similar" drug, which has acted in the same direction as nature, as a supplementary and specific stimulus upon the reactive powers of the organism.
To make possible the search for the remedy most suited to producing the similar disease, it is necessary to know with exactness the effects of individual drugs on the healthy man.
Carried out with the necessary scientific rigor, these investigations have among other things demonstrated that the action of a drug always tends to unfold in two well-distinct phases: the first, which Hahnemann called "primary action" and attributed to the toxic action of the drug, hence, practically, to the dose employed; the second, or "secondary effect," which Hahnemann identified with the organism's effort to free itself from the disturbances that the drug has provoked. It is therefore essentially to the secondary effect, that is, to the vital reaction, that the salutary action of the remedy must be attributed; and since the vital reaction is excited by small stimuli, while it remains suffocated and even annihilated by stimuli that are too strong (the Arndt-Schultz law of fundamental biology), a correct dosage will have to reduce the primary action to a minimum, hence reduce the doses to a minimum. Such is the chief reason why homeopathy preferably employs its drugs at minimal and often imponderable doses; but this is to be regarded only as a logical corollary of the law of similars, and not as a fundamental cornerstone of the system, as has been erroneously believed by some.
In any case, the minimal dose of homeopaths is not the result of a pure and simple attenuation. When Hahnemann, in fact, progressively diminishing the doses in the course of his experiments, had passed beyond the boundaries of the imponderable, he began seriously to fear that he had also passed beyond the boundaries of the reasonable. His doses, by then negligible, were no more than extremely dilute solutions; with no other claim than that of ensuring a uniform distribution of the remedy in the solvent, he then took up the habit of diluting systematically according to a progressive scale (decimal or centesimal) and of giving the bottles a certain number of shakes at every passage from one concentration to that immediately lower. Following this system he saw that the therapeutic action of his solutions persisted not only specifically, but even to an increasing degree; and on the other hand this intensification of the drug's activity did not occur when the shaking of the solutions was omitted. Hahnemann gave this procedure the name of "dynamization," to indicate that by it one tends to liberate from matter the immaterial forces contained in it. It is in reality the daily confirmation of biological control that authorizes us to think, with Hahnemann, that the practice of dynamization can reveal in drugs specific energies and latent biochemical affinities, perhaps through a modification and disintegration of their original physical structure.
Apart from any hypothesis on the physical state to which the drug may attain by means of Hahnemannian dynamization, it is proven that the infinitesimal dose shows itself active only when the remedy is perfectly "homeopathic" to the clinical case, that is, when the picture of symptoms that it can provoke in the healthy organism is very similar (similimum) to that of the patient. It is therefore indispensable that the patient be examined thoroughly, not only with accurate inspection of the organs and functions affected, but also with the study of his subjective sensations and his mental symptoms, above all giving value to those peculiar and individual facts which, being characteristic of his mode of reacting, better define his morbid personality. The homeopathic physician cannot use the pathognomonic symptoms of the disease, which serve solely for clinical diagnosis, but only the pathognomonic symptoms of the patient, the only ones useful for the purposes of psycho-bio-physical diagnosis, which in homeopathy is identified with the diagnosis of the remedy. Homeopathic practice therefore requires a twofold diagnosis, and confronts the disease not with a remedy for each symptom (as is done in symptomatic treatments), but by administering that remedy which by itself repeats the entire morbid syndrome, with the best possibilities of polyvalent action, hence specific in the most ideal sense of the word.
The scientific updates, the new means of clinical investigation, and the overall evolution of medical science and therapy have not only left the edifice built by Hahnemann intact, but in many cases have strengthened it with authoritative confirmations. New theories and new therapeutic systems appear and disappear every day; Hahnemann's doctrine, perhaps the only one to have known the snares of opposition and criticism from its very first dawn, appears among the very few that have preserved their vitality and improved their efficiency.