A Brief History of Potentisation


Key words: potentisation, succussion, LM potency, trituration, Hahnemann



Amply supported with a wealth of quotation material in footnotes drawn from a range of authoritative sources, this short article delineates a brief history of the processes used to prepare homeopathic drugs and the evolving rationale of Hahnemann’s methods.



Though Hahnemann is reported to have employed small doses compared to his colleagues, (1) he did not actually start potentising drugs until about the year 1798-9, (2) eight years after the first drug proving. (3) For example, he recommended very tiny doses for Belladonna in the treatment of Scarlet fever in an essay of 1801 (4). Clearly about this time, and for several further years, he was experimenting in general with dose reduction. (5) It appears this was in order to diminish the potent and troubling side-effects these new homeopathic drugs were capable of exciting when given for the correctly matching sickness. (6) Not resting content with random dilutions, he wanted a standard graduated scale for all drugs. In due course he developed the centesimal or C scale where one part of the drug is diluted in 100 parts of non-medicinal solid or liquid, either as one grain of solid in 100 grains of milk sugar (lactose) or as one drop of plant tincture in 100 drops of 30% alcohol. (7) At each stage of serial dilution he empirically found that the therapeutic power of the remedy is enhanced if the liquid is agitated violently or succussed. (8) In brief this is how the vast bulk of homeopathic remedies were first prepared and most of them still are.


By mid-century, other homeopaths had developed the decimal or X scale, diluting the drug 1 in 10, which was very popular in European homeopathy c.1850-1930. (9) Quite suddenly, in 1829, Hahnemann insisted that all homeopaths should use 30c as the standard potency in treatment. (10) However, towards the end of his life Hahnemann developed the LM or Q scale (Q stands for quintamillesimal) using 1 drop to 50,000 drops. These are usually given in liquid form. He used this method from the year 1840 to his death in 1843 (11) and it has more recently come back into fashion. It is reportedly the gentlest method extant, apparently inducing the fewest side-effects or aggravations. (12) Along with these LM and liquid doses, in the last fifteen years of his life, Hahnemann made extensive use of Olfaction or the smelling of remedies. (13)


As we can see from this brief survey, potentisation was a method Hahnemann was obliged through experiment to adopt in order to obtain safer and gentler curative action from single drugs (14) when they are employed on the basis of similars (15). Apart from provings, homeopathy can thus be seen to encompass single drugs, similars, small doses and the case totality that is holistically inherent to the notion of medical similars. Though his views on dosage evolved considerably through time, it is apparent that this pattern flowed entirely from his penchant for endless experimentation, his gift for sharp observation, impulses which were firmly yoked, as always, to clinical practice. In his final years in Paris, and through his experience of using Olfaction and LM potencies in liquid doses, he felt he had virtually resolved and perfected to his own satisfaction, the whole question of homeopathic posology.



1. Hahnemann used tiny doses of Mercury for syphilis (Robert E Dudgeon, Lectures on the Theory and Practice of Homeopathy, London, 1853, p.392); his early doses were small but by no means infinitesimal. (Dudgeon, p.117) "In his early years of practice Hahnemann used doses comparable to those of his colleagues." (Harris L Coulter, Divided Legacy, 3 vols, Wehawken Books, Washington USA, vol. 2, 1973, p.400) In 1797-8 he still "continued to use appreciable doses. But he used single remedies.” (Thomas L Bradford, 1895, Life and Letters of Hahnemann, Jain Indian Edition, 455) In the late 1790s "the doses he gave were by no means small, far less infinitesimal." (Dudgeon, 117) Even in 1798 "we find him giving...full doses." (Dudgeon, 117)


2. The first potentisations date from c.1798 and then in 1799 he suddenly announced infinitesimal doses. (Richard Haehl, 1922, Samuel Hahnemann His Life and Work, 2 vols, Jain, India, 1, 312) "We cannot fail to be struck by the sudden transition from the massive doses he prescribed in 1798 to the unheard-of minuteness of his doses only one year later, and we can but guess the causes for this abrupt transition." (Dudgeon, pp.395-6) "In 1799 he suddenly announced without particular explanation very small and so-called infinitesimal doses." (Haehl, Vol. 1, p.312) "In 1799 he first announced the principle of the infinitesimal dose, and after 1800 his dose sizes were gradually reduced." (Coulter, vol.2, p.400) Numerous examples of Hahnemann's early small doses are given in Dudgeon, pp.392-6; " was not long before Hahnemann’s persistent experimentation revealed that dilution and succussion of remedies somehow rendered them more effective." (Rima Handley, In Search of the Later Hahnemann, Beaconsfield, 1997, pp.7-8) Hahnemann "gives no reasons for his sudden change from appreciable doses in 1798 to comparatively minute ones in 1799." (Bradford, 458)


3. The very first homeopathic proving (that of Cinchona) was conducted by Hahnemann in 1790. (Haehl, 1, p.35; Dudgeon, pp.176-7 & pp.338-9)


4. His essay was 'Cure and prevention of scarlet fever,' publ: Gotha: Becker, 1801, 40 pp. In it he recommends Belladonna in a very tiny dose. "It is in his little work on Scarlet Fever, published in 1801, that we have the first forebodings of an unusual mode of preparing the medicines...the dose of Opium there very small compared with the ordinary dose...the object of this dilution was to diminish the power of the medicine chiefly...for patients of very tranquil disposition." (Dudgeon, p.338) "For the cure of the first stage of Scarlet Fever (published in 1801) the dose of Belladonna prescribed was only the 432,000th part of a grain of the extract, a quantity intermediate betwixt our 2nd and 3rd dilution." (Dudgeon, p.394) He gave a child "the one four hundred and thirty-two thousandth part of a grain of Belladonna, with the result that in about twenty four hours she became Hufeland’s Journal, 13.2, January 1801, he published ‘On Small Doses of Medicine in General and of Belladonna in Particular’...and supports his doses of Belladonna previously given." (Bradford, p.70) His enemies "ridiculed his minute doses of Belladonna," (Bradford, 70) which he prescribed for scarlet fever.


5. Hahnemann "first began to talk about dilution in 1801," (Handley 122); this involved one drop of tincture "mixed thoroughly with 500 drops of spirits of wine." (Handley 122) Having then "accepted the principle of dilution, he experimented for a long time with doses both dilute and crude." (Handley, 122) In due course, "he varied the dilutions, using many different ratios of substance to diluent." (Handley, 122) "The theory of dilution underwent very little change in the year 1802," (Dudgeon 315) but "a peculiar change is noticeable in the prescriptions of the year 1803... (where we see him) making experiments with certain medicines of considerably higher dilutions." (Dudgeon, 315) He was clearly "still groping and experimenting hither and thither." (Dudgeon, 315) Then in 1799 comes "the sudden introduction of infinitesimal doses." (Bradford, 456) "In 1800-1 he was using 1/18,000 of a grain of Aconite, 1/2000 of a grain of Capsicum, Pulsatilla in 1/400,000 or 1/1,600,000 of a grain, Chamomilla 1/3,840,000,000 of a grain." (Haehl, 1, pp.314-5) "In his essay announcing the discovery of a new therapeutic principle, published in 1796, no allusion is made to any doses different from those in ordinary use...and in his writings up to 1801 nothing is to be found to lead us to suppose that there was anything exceptional in his mode of employing drugs." (Dudgeon, pp.337-8)


6. Hahnemann's first case of aggravation from using a homeopathic drug came in 1797. (Dudgeon, p.117) "Hahnemann…(became) perplexed by the aggravations resulting from ordinary doses." (Stuart Close, The Genius of Homeopathy Lectures and Essays on Homeopathic Philosophy, New York, 1924, p.218) "This reduction (in dose) was apparently due to Hahnemann’s observation that medicines administered in substantial amounts according to the law of similars caused severe aggravation of symptoms." (Coulter, vol. 2, p.400) Lower doses were envisaged by him to render the remedy safer, "since the remedy's capacity to imitate and hence provoke or elicit symptoms similar to (the disease), put too much strain on the patient, if those symptoms were recreated too strongly." (Handley, 122) The "first very distinct and decided case mentioned by Hahnemann of a real homeopathic aggravation, followed by a well-marked curative effect...was published by him in...1797." (Dudgeon, 117) But even in 1801, "the homeopathic aggravation is not yet taught as a doctrine, but merely incidentally alluded to." (Dudgeon, 118) It was "the homeopathic aggravation, that is the increase of all important disease symptoms which followed upon the administration of the 'specific remedy'... (that) induced him to gradually decrease the dose." (Dudgeon, 311) With regard to dosage it was "the aggravation after strong doses," (Dudgeon, 315) that drove him ever further into drug dilution. The homeopathic aggravation mentioned in 1797 is noted by Bradford in page 454. He denounced larger doses which, "he says, cause medicinal aggravations." (Bradford, 456)


7. The centesimal scale is described in Haehl, 1, p.322; 2 drops of plant juice should be added to 98 drops of spirit of wine (Dudgeon, p.345); In "seeking to find a dose so small that it would not endanger life and desiring to accurately measure his degree of dilution so that he might repeat or retrace his steps, (Hahnemann) invented or adopted the centesimal scale." (Close, p.218) "Hahnemann's idea at first was simply to reduce the "strength" or material mass of his drug, but his passion for accuracy led him to adopt a scale, that he might always be sure of the degree of reduction and establish a standard for comparison." (Close, p.216)


(8) The "first decimal potency (1x) consisted of one part of mother tincture and nine parts of an alcohol-water mixture...after each dilution...the solution was succussed, that is shaken vigorously with impact," (Trevor Cook, Samuel Hahnemann Founder of Homeopathy, 1981, 97) Impact was achieved, "by Hahnemann banging the vial containing the solution several times against a leather bound book, but nowadays this is achieved by mechanical means." (Cook, 97) He describes succussion as a "diligent shaking for a minute at a time," (Dudgeon, 338) or "being rubbed up with it, and then strongly shaken for five minutes." (Dudgeon, 339) He adds that any remedy "vigorously shaken, will possess enormous power." (Dudgeon, 339) For example, he claims that "one single drop of a tincture, intimately mixed by vigorous shaking with a pint of water and given in doses of two ounces at a time, every two hours, will produce four times as much effect as eight drops of the tincture taken at one dose." (Dudgeon, 342) Through "trituration and succussion, he says, the medicinal power of medicines may be increased almost to an infinite degree." (Dudgeon, 346)


He asserts that succussion "actually increased the power and energy of the drug, or even conferred on it entirely new properties." (Dudgeon, 347) He states that drugs should be "shaken ten or more times," (Dudgeon, 347) for "he recommends ten succussion strokes as the rule for each dilution." (Dudgeon, 348) In spite of many variations, in general he appointed "ten strokes for each dilution as standard." (Dudgeon, 349) He prepared drugs "by vigorous shaking or trituration," (Dudgeon, 324) that is by "trituration, a uniform mixing, dilution...of the medicinal substance," (Dudgeon, 324) and there resulted an "increase of power by succussion; the more the medicine was succussed when prepared, the stronger its effect. Only by dilution in conjunction with the vibration of shaking does dynamization or potentising arise." (Dudgeon, 324) In preparing these dilutions he recommended the homeopath "render union perfect by diligently shaking the liquid...for a minute," (Bradford, 457) at every stage in the elevation of potency.


9. Decimal scales were in use throughout the 19th century, especially in France and Britain: for Dr John "Drysdale (1816-1892)…low dilutions did best and he found no advantage above the 3rd decimal," (Frank Bodman, Richard Hughes Memorial Lecture, Brit. Homeo. Jnl 59, 1970, pp.179-193; p.184); until "Mr (Clarence Granville) Hey (c.1875-c.1950) came to the hospital (c.1905), anything above a 3x potency was anathema to Dr Burford…(but) he altered his views and gradually used 6, 12, 30 and 200, and finally he used the highest potencies." (Dr George Burford Obituary, Brit. Homeo. Jnl 27, 1937, pp.164-175; p.172) For example, conservative 'old guard' British homeopaths in the 19th century prescribed remedies "in low potency, usually 1x or 3x, but mother tinctures were used regularly." (Bernard Leary, M Lorentzon, and A Bosanquet, "It Won’t Do any Harm: Practice & People at the London Homeopathic Hospital, 1889-1923." in Robert Juette, Guenter Risse and John Woodward (Eds.), Culture, Knowledge and Healing: Historical Perspectives on Homeopathy in Europe and North America, Sheffield: Sheffield Univ. Press, 1998) Those "materialistically minded (homeopaths) restricted themselves to the crude tinctures and triturations, or the very low dilutions, ranging from 1x to 6x." (Close, pp.183-4) It seems that the decimal scale was first introduced by Dr Hering, see:

10. In spite of numerous attempts to do so, Hahnemann finally "decided that it was impossible to establish the optimum potency for each remedy." (Handley, 123) In "1833 and 1834...he had come to the conclusion that...a single dose brought about cure too slowly, and suggested that more frequent repetition would be more expeditious." (Handley, 123) However, "Hahnemann himself felt, in 1829, the urgent necessity of a limit in potentisation and declared the ultimate degree of dilution to be the 30th centesimal potency." (Haehl, 1, p.321) "In the year 1829 Hahnemann came upon the strange idea of setting up a kind of standard dose for all curative remedies used in homeopathy. This was to be the 30th centesimal." (Haehl, 1, p.322) Regarding 30th potency, in a letter to Dr Schreter dated 19 June 1826, he recommends the 30th potency: "I have advised and in dynamising all antipsoric medicines up to 30." (Bradford, 192)


11. Liquid remedies were first introduced in 1834 (Handley, 135) and "he seems to have begun to use the LM potency in his practice towards the end of 1840." (Handley 142)


12. "The correct dose of the LM potency in medicinal solution produces a non-aggressive primary action, no aggravations, and a long enduring gentle curative action."


(13) Olfaction "was a method he had first introduced in 1829.” (Handley, 133) In the technique of "olfaction: the patient was asked to inhale the remedy...a method he had first introduced in 1829 and never subsequently abandoned." (Handley, 133)


(14) In 1800, in the Preface to his translation of the Thesaurus medicaminum -- a New Collection of Medical Prescriptions, Hahnemann derided allopathic drugs as being "unnatural, contradictory and opposed to the object for which they are designed." (Bradford, 71-2) He then argues "against compound prescriptions and in favour of single remedies." (Bradford, 72) He "pleads against the use of so many drugs in one prescription." (Bradford, 72)


(15) From 1796 onwards "he selected his remedies from the standpoint of similarity, still administering, fairly large doses." (Haehl, 1, 311) "The physician prescribes individually by the study of the whole person according to their basic temperament and responses." (Cook, 97) He based his practice on "the similarity between disease and remedy, and he only prescribed one medicine at a time." (Dudgeon, 315) He succinctly described 'similarity' as "a remedy so capable of producing a counterpart of the symptoms," (Bradford, 70) of a sick patient.