Views of various authorities on selection of potency


Dr. J. D. Patil


M.D.(Hom) P.G. Director, DKMM Homoeopathic Medical College, AURANGABAD

Director of Student Welfare 'Maharashtra University of Health Sciences, Nashik'.


            Potency and Potency Selection is unique to Homoeopathic system of Medicine. Homoeopathic posology is different from other systems of medicine as the prescription is based on natural law of similars and on single drug and minimum dose. (Simplex simili minimum). small doses and homoeopathy are commonly regarded as synonymous terms.

            Posology (from the Greek word’posos’=how much) means the study of dosage.

            Potency (from Latin word ‘potentia’) means power, force, strength.


            After discovery of the new system based on law of similars Hahnemann first used only similar medicines in material doses from 1790 for almost 8 years and found out severe aggravations in the patient in spite of similarity in selection of the drugs.  Then he started reducing the dose by diluting the medicines to 2x, 4x, 2c. According to peter Morrel’s research in 1799 Hahnemann used 5x, 6x, 3c and 8x.  In 1801 Hahnemann wrote an article on the power of small doses in general and of Belladonna in particular in treating scarlet fever.  In 1803, 12c appears for the very first time in 1805 appeared the 18c potency which potency Hahnemann used as favorite thro’ his long career.  In 1816, 30c makes its first appearance which remained his most extensively used and most highly recommended potency of all the time.  By this process of dynamization all the material substances of the drugs seems to dissolve and be transmuted into pure medicinal spirit.

            In 1828 Hahnemann explains about higher dilutions in the preface of Thuja in 5th volume of Materia Medica Pura.  In the preface to the 5th volume of the chronic diseases Hahnemann explains about the power of dynamization “It is absolutely necessary to dilute medicines in order to be able to potentize or dynamize them, for the greatest amount of succussion and trituration of substances in a concentrated form will not enable us to liberate and bring to light the more subtle part of the medicinal power that lies still deeper”.

            Hahnemann introduced his centesimal scale of potencies (Medicaments a la gouttee) in his 4th edition of organon, and in his 6th edition of organon (1842 but seen limelight in 1921 to the Meical fraternity) he introduced the 50 millesimal potencies (Medcamentum a globule).  There are different views of various authorities on selection of potency as follows:



§         By minute subdivision energy is liberated from inert mass-bulk-weight; from things palpable and manifest to our grosser senses.

§         We are at last beginning to realize the potentialities of the intangible and the imponderable.

§         But the most sensitive thing in the world is the diseased call or tissue for the remedy of like symptoms, in infinitesimal subdivision.

§         Homoeopathy never wants to do anything to a patient: only to stimulate his own reactive powers, and so cause him to cure himself.

§         For Hahnemann, disease was merely the rebelling Vital Force against noxious agents, inimical to life : and he taught the cure can only come from the stimulated reaction of Vital Force against disease.

§         Again, Hahnemann tells us that the smallest possible dose of a homoeopathic medicine will operate chiefly upon the diseased parts of the body, which have become extremely.  BERNOVILLE of a stimulus so similar “to their own disease”.

§         Most of the homoeopaths agree on the point that the lower dilutions act soon, superficially and for a short time; the high dilutions act slowly, deeply and for a long time.

§         It seems that the laws relating to the homoeopathic dose are rather some corollaries of the law relating to the intensity of excitations caused in the living organism.

§         In practice this is very important and should be considered with a supple mind because the excitation differ according to the remedies.

§         But we must insist on the point that, while diluting the medicines the homoeopaths have discovered a capital principle which is the duration of the action of homoeopathic medicines.

§         When you begin to treat a patient with a high dilution the duration of its action is not very long. Take for example: you administer Lachesis 200, to a patient who has never been treated or who is having homoeopathic treatment for the first time.

§         In such a case the duration will not be more than 7 to 8 days.  The negative phase is 24 hours’ the positive phase begins on the 2nd day; amelioration continues for 6 days and from the 6th day the amelioration begins to fall and the patient feels less better.

§         You repeat the dose and as gradually you go on repeating the dose even in the same dilution the duration of its action will increase.  If instead of giving Lachesis 200, you apply 1,000, the duration of action will be 15 days of positive phase and next you will have one month with another dose of M and you will obtain a positive phase for 2 to 3 months with Lachesis 10,000 Korsakow.

As regards the lower dilutions, they are to be applied rather in acute cases because they act superficially and for a short duration.

     On the other hand for the drainage of a chronic case we will get a real hierarchy of actions by giving a high dilution which acts for a long time, followed by some functional remedies which are repeated every day or at an interval of two days for the reason that their action is short lasting.

In summary

§         The high dilutions have a negative phase of aggravation for one or two days followed by a slow amelioration continuing for a long time.

§         The lower dilution acts for a short time.  It acts superficially and it should be repeated.

§         The mixture of the two kinds of dilutions give a result intermediary between the two.




§         To determine the potency to be given has been much more difficult then to determine the repetition of the dose.

§         The method has been much the same as that employed in determining the repetition of the dose, viz., to study the reports of provers and patients (Clinical cases), and to ascertain from our encyclopaedias and journals the potency used when the group of symptoms similar to the one under consideration was caused or cured.

§         In this study of both provers and special attention should be given to the make-up.

§         A higher potency should be selected for the markedly neurotic and the highly susceptible patients, than for the dull, sluggish, unimpressionable ones.

§         Another element enters into deciding on the potency, and that is whether the case is an acute or chronic one.

§         The potency should always be higher and the time waiting to determine whether the remedy given is acting or not should be much longer for chronic than acute cases.




The three medicine chests of Hahnemann were then in the possession of Dr. Richard Haehl, of Stuttgart.

     List of the remedies they contain with special reference to the degrees of potency



§         These are placed in two polished wooden boxes.

§         The larger one is 48 cm. long and 30 cm. wide, and contains altogether 600 small glass bottles filled with globules.

§         The smaller box is 26 cm long and 22 cm wide and contains 288 small bottles.

§         The degrees of potencies are indicated in Hahnemann’s own way.

§         II means one billionth part = 6 cent. = 12 D

§         VI means one sextillionth part = 18 cent. – 36 D

§         VIII means one octillionth part = 24 cent. = 48 D.

§         X means one decillionth part = 30 cent. = 60 D

Some drugs for example.

§         Acidum benzoicum                   6             18           30        -

§         Acidum hydrocyanicum             6             18           24        30

§         Acidum muriaticum                   6             18           24        30

§         Acidum nitricum                        6             18           24        30

§         Acidum phosphoricum              6             18           24        30

§         Acidum sulphuricum                  6             18           24        30

§         Acidum tartaricum                    6             18           24        30

§         Aconitum                                  6             18           24        30




§         A large polished wooden case inlaid with ivory, 63 cm. long and 342 cm. wide affords room for 1716 glass tubes The remedies contained therein are prepared by the new method of potentising and designed as medicaments aux globules with 0/1, 0/2, 0/3. etc.

§         Most remedies are kept in stock in ten different degrees of potency (I to 10); only a few, as for instance, Mercurius solubilis, Sulphur, and a few others are potentised up to the 30th degree.

§         The case also contains a large number of full glass tubes with an altogether different kind of designation which has not yet been understood. Unfortunately a large part of the contents seem to have been lost.




§         In the most acute disease, and in chronic diseases combined with debility, in which the general derangement of the organism is obvious the smallest doses are to be given.

§         These smallest doses are equivalent, in the amount of medicinal substance they contain, to the 2nd and 3rd dilution of the ordinary or centesimal scale.

§         In what are called local diseases-those chronic diseases, to wit, where the morbid affection is localized and the general system does not seem to be much implicated-the doses must be gradually increased in strength.

§         It does not appear what Hahnemann understood by these stronger doses, but as he wrote for the ordinary practitioners in a journal of general medicine, I presume he meant by this expression such doses as were commonly in use.

§         It is evident that at this time he did not contemplate the exclusive treatment of diseases by means of specific or homoeopathic medicines, but that he admitted the propriety of the palliative or antipathic treatment in certain cases, and that for such treatment he considered the very largest doses used in ordinary practice to be necessary.

§         The proper dose must be determined—

§         1.By the peculiar nature and essential character of the medicines. Their physiological provings throw all the light we possess upon their energy, intensity, extensity and duration of action.

§         Among the medicines which, even in large doses, display great energy and intensity along with a short  duration of action, are, aconitum, chamomilla, camphor, moschus, ignatia, ipecacuanha, hyoscyamus, coffea, stramonium, laurocerasus, sambucus, opium, etc.

§         Those that have a less violent, but more intensive, penetrating, and longer-lasting action, are almost all the mineral medicines, the mineral acids, and not a few vegetable substances.

§         The most energetic and intensively acting medicines and intensive medicines in the medium dilutions; the least energetic and intensive in the lowest dilutions and crude substance.

§         The first class includes all our so-called heroic medicines; such are, belladonna, bryonia, arsenicum, calcarea, kali, lachesis, lycopodium, mercurius corrosives, natrum muriaticum, phosphorus, sepia, silicea, sulphur, rhus, etc.

§         The second class, which should generally be used in the medium dilutions, included cannabis, china, euphrasia, coffea, arnica, asafetida, agnus, bismuth, capsicum, chamomilla, chelidonium, crocus, dulcamara, digitalis, gratiola, hepar, ipecacuanha, laurocerasus, ledum, mezereum, phosphoric acid, nux moschata, oleander, opium, rheum, Sabina, secale, senega, spigelia, squilla, tabacum, thuja, veratrum, etc.

§         The third class, which generally require to be used in the lower dilutions and crude substance, comprehends ferrum, verbascum, camphor, moschus, castoreum, viola odorata and tricolor, taraxacum, trifolium chelidonium, etc.

§         The second determining circumstances is the nature and character of the disease to be cured.

§         Diseases that display in all their phenomena great energy and intensity, rapidity of evolution, attack the most important organs, betray much malignancy, and threaten the integrity of the whole organism, or of certain parts of it, demand and energetic and rapid medicinal influence.

§         To this category belong almost all the acute diseases, inflammations, gastric, bilious, catarrhal, rheumatic, typhus, fevers.

§         Nervous fevers and nervous rheumatisms, on the contrary, demand the higher dilutions.

§         Chronic diseases demand, as a rule, the higher dilutions, but there are exceptions to this, in the case of those diseases, namely where, along with inveteracy and long duration, there is torpor of the ganglionic system, as in the case of hypochondriac diseases, where the patient has led a dissipated life.

§         In hysteria also the smaller doses can often not be borne, especially in those cases where in some parts the irritability is abnormally increased, in others abnormal torpidity is present.

§         In those cases we sometimes find that neither the high nor the low potencies do any good. In other cases of hysteria we sometimes observe the best effects from the high dilutions.

§         Where there is great irritability of the cerebro-spinal system, there is often little susceptibility to medicinal influences, and, on the contrary, a high degree of susceptibility often co-exists with great torpor and even partial paralysis of the nervous system.

§         Disturbances of the mental state of a chronic character often demand the utmost caution in the choice of the dose.

§         Often the smallest dose suffices to restore the lost balance of harmony of the most chronic description, in other cases large and repeated doses are required.

§         Diseases of the mucous membranes of  the alimentary canal, of the uropoietic and sexual organs, and of the respiratory passages, may be treated at once with the medium dilutions, and

§         The lower dilutions may be had recourse to where there is great atony and torpor, especially if this has lasted long.

§         Neuralgias and spasmodic affections sometimes require high, sometimes low dilutions.

§         Syphilis and its various developments demand the lower dilutions and stronger doses of the appropriate medicine;

§         But the most inveterate cases never require the mercurials in the crude state.

§         Chronic gout demands great circumspection in the selection of the dose; the smallest doses often cause intolerable aggravations.

§         Chlorosis requires iron in large and repeated doses, but other medicines in the highest dilutions.

§         The other determining circumstances in the selection of the dose detailed by TRINKS; they are- -

§         3. The individuality of the patient.

§         4. The constitution.

§         5. The sex. The female is most susceptible, and therefore requires the smallest doses.

§         6. The temperament. The melancholic, sanguine, and choleric temperaments display the greatest  susceptibility, the lymphatic the least.

§         7. The manner of life of the patient.

§         8. His idiosyncrasies.

§         9. The epidemic and endemic influences.

§         10. The influences of climate. The inhabitants of warm climates seem to possess a greater susceptibility for medicinal influences then those of more temperate and colder climates.


DR. KOCH, in his great work On Homoeopathy, (Die homoeopathic, p.586.) has given the following are the practical rules he lays down for the dose:-

§         The more similar the remedial power (the pathogenetic effects of the medicine) to the disease, the more certain will be the cure, and the smaller, within certain limits, should be the dose.

§         The less similar the medicine, the larger should be the dose, but the cure is not so certain.

§         The more similar the medicine, the more hurtful is a large dose.

§         The greater the susceptibility, the less should the dose be, and vice versa.

§         The more intensive the exciting cause, the more similar and stronger, quantitatively speaking, must the medicine be.

§         The more intensively, rapidly, and energetically the morbid process goes on, the more necessary is it to select the remedy accurately and to give a larger dose, whilst in morbid processes of less intensity and rapidity a smaller dose is necessary.

§         There is and can be no normal dose for all medicines, for all diseases, and for all patients; for medicines differ vastly among themselves in respect of power, diseases in point of intensity, and patients in point of susceptibility for medicinal impressions.

§         These three points must all be attended to in our selection of the dose or dilution of medicine we prescribe, and though we are still considerably in the dark with respect to the suitable dose of a remedy for the different circumstances for which that remedy is indicated, I think this darkness has been partially dispelled by the experience of so many homoeopathic practitioners extended over so many years.




§         The elements of similarity for the selection of similar remedy:

§         The generic similarity

§         The specific similarity

§         The individual similarity

§         The drug should be administered as a rule singly, rarely, constitutionally and minutely.

§         A real dynamization is required in those substances which are inert in their crude state when rubbed up with some indifferent vehicle a fine division of particles and the substances become active.

In 1839, Hahnemann tells that it is absolutely necessary to dilute medicines in order to potentise them by this process the subtle medicinal power that lies still deeper is liberated and brought to light.

There are two criteria in mind in the choice of the Dose:

1.  To avoid aggravation and collateral disturbances,

2.  To develop the peculiar properties of durgs.

In the choice of dosage – R. Hughes approach is different.

In the very acute typical disorders- such as fevers, inflammations, catarrhs, neuralgias, spasms etc.- which constitute the bulk of daily practice, the fist object is to be sought (as to avoid aggravation or collateral disturbances).

The medicines you sought to administer are already acting in their crude state, your only care need be to protect your patient from the activity of the medicinal action, to see that their physiological action be wholly absorbed in their therapeutic actions.

For this purpose – moderate potencies are sufficient. You require to carry in your pocket case the remedies





1.  The sphere of action of a medicine continually enlarges the higher the dynamization is carried

     a)  This is most striking in those remedies which in their raw state excite few symptoms - e.g.  
           calc; silicea; nat mur; aurum; alumin met etc.

     b)  They produce more effects in 30th potency when compared to the effects they produce in 2nd
           or 3rd trituration, their power develop further with every additional dynamization.

     c)  Thus they are indicated in ever increasing number of ailments as their homoeopathic stimuli

     d)  Therefore in chronic ailments they hasten the cure.

2.  In acute diseases the after effects or curative effects appear more quickly.

3.  By continual dynamization, remedies are more and more withdrawn from the laws of chemistry.

     e.g. A dose of phosphorus highly potentized can lie in a paper envelope in a desk and if taken  
     after an year will show the full medicinal power of unchanged, undecompsed phosphorus itself.
     These powders showed unchanged medicinal action even after period of 12 years or so and had
     their full success.

4. A defective diet frequently spoils the best cures- always does less damage the higher the
     dynamization is., and least of all if a minute dose dissolved in water and every time shaken a new,
     is taken several day in succession.

5. The specific dynamic powers will become active, while the gross material (poisonous and
     destructive) properties are not manifested.

6. The higher dynamization can never be used as deceptive palliation which are useless as to any    
     curative effects and always extremely injurious.



© Copyright With Dr. Pawan S. Chandak