History and development of Synthesis Repertory

Dr Abhijit Chakma 

Difficulty in finding the simillimum quickly made many homoeopathic practitioners to venture into preparing an index to the symptoms of our Materia Medica i.e. Repertory. In process of its evolution from beginning very recently we got Synthesis Repertory. A brief study on Synthesis Repertory though this article is an attempt to show its evolution and unique features by which we can easily overcome our present day to day problems in clinical practice and thus utilize the pathological general symptoms, clinical symptoms, poisoning conditions.

Keywords: Synthesis Repertory; Frederik Schroyens; Kent; Evolution; Philosophy; Sources; Gradation.

Full name of the repertory: Repertorium Homoeopathicum Syntheticum. 

Author: Dr. Frederik Schroyens. He was born in January 12, 1953 in Mechelen, Belgium. Schroyens is a 1977 medical graduate of the State University of Gent (Belgium) and a 1978 graduate of the one-year Homeopathic Training Course at the Faculty for Homeopathy in London (MFHom). Dr. Schroyens was one of the first RADAR users in 1986 and became enthusiastic about the increasing possibilities computer science offers to Homeopathy. Because of his dedication to the program, he became the Homeopathic Co-ordinator of the RADAR Project.

From Greek word syntithenai – to put together; from syn + tithenai to put, place.

First Known Use: 1589


  • The process of putting together separate parts to form a complete whole.
  • Making a whole out of parts.
  • The combination of separate elements in a whole.

SYNTHESIS is nothing but the on going process of collection and compilation of symptoms converted into rubrics with corresponding medicines and their gradations from various sources.

Changes are taking place in all walks of life, all over the world. A system which is immune to change cannot stand for a long period of time. Each system should uphold the changes happening in the environment and adjust itself to the changing condition, so that, it can make the system vital. Absence of such changing will hamper our system. But it is clear to all of us that changing should be constructive one and without compromising on our basic principles. 

Repertories are developed to help the homoeopathic doctors in comparative study of materia media and in indicating some group of similar medicines to a given case.

Since, Hahnemann, who first felt the necessity of repertory, till date we have many repertories available in the market. In this regard, we must not forget Clemens von Boenninghausen, who first created the usable repertory in 1832.

Different authors expanded on previous versions of this repertory, e.g. T. F. Allen (1880; Symptom Register), Jahr (1835; Symptom Repertory), Lippe (1854; A Repertory of Comparative Materia Medica). Some created completely new structures as did Gentry (1890; The Repertory of Concordance) and Knerr (1896; The Repertory to Hering’s Guiding Symptoms).

The glory of development of repertory came to its pick by the publication of Kent’s repertory fascicle by fascicle from 1897 to 1899. For a few decades, no other repertories succeeded in taking up the challenge of progress after the publication of successive editions of Kent’s repertory. But later on after the 6th edition of Kent’s repertory in 1957 several Indian editions have been printed, which contain an unacceptable amount of mistakes. In this regard we have the comment of Dr. George Vithoulkas in foreword to the Synthesis Version 5. He says- “Kent’s repertory, even if it is the best so far, contains a lot of errors; its structure and its logic are not always maintained, etc. I felt there was no good reason to reprint all the same errors once more, even with lot of additions, because this was done already too often by other so called new repertories.”

It was the era of development and publication of new repertories by different authors mainly based upon the Kent’s philosophy. These new repertories are still coming with some modifications and additions. Repertories like Synthetic (1973), Synthesis (1987), Murphy (1993; Indian edition 1994), Complete (1996) etc. are the fruits of this new era.

In 1973, Barthel and Klunler started the publication of a 1st version of their ‘Synthetic Repertory’, adding information from 14, later from 16 authors to the five (5) main chapters of the repertory (Mind, Generals, Sleep & Dreams, Male and Female Sexuality). They did not expand their work to more authors or chapters; their repertory was considered a new reference by many.

So it was this background that we needed a new, more complete, informative repertory to overcome the pitfalls of previous repertories.

Dr. Frederik Schroyens ultimately did this job in collaboration with the leading homoeopaths throughout the world leading to the development of synthesis repertory. Synthesis is a repertory linked to RADAR (Rapid Aid to Drug Aimed Research) project. It is based on 6th American edition of Kent’s repertory and contains all its rubrics and remedies. Since 1987 Synthesis has been used as database for RADAR. It has been commented upon and there by improved over and over again. Indeed not only additions of an increasing number of authors but also correction of existing data have been integrated. 

Synthesis is the product of a continuous teamwork with superb technology. It is the printed version of RADAR computer programme. This repertory has set a new standard by adding many information and continuous verification by its users. It is the latest among all repertories. Synthesis repertory is based on 6th American edition of Kent’s repertory, and contains all its rubrics and remedies maintaining its philosophical background also. The synthesis repertory linked to the RADAR project. RADAR was first developed as research project at the University of Namur (Belgium) under the supervision of Jean Fichefet. He was the professor of mathematics in the department of computer science at the same university. He became interested in homoeopathy after the miraculous cure of his son by homoeopathic medicine. Dr. Frederik Schroyens became the homoeopathic co-ordinator for the RADAR project. He had outlined a request for collaboration in the year 1986. Dr. Frederik Schroyens and his team sent charter to all leading homoeopaths who were concerned with evolution of homoeopathy through the software version. Since 1987 Synthesis is used as a database software programme, i.e. RADAR in daily practice of leading homoeopaths. This book is primarily based on 6th edition of Kent’s repertory and has been commented upon and improved from time to time by various leading practitioners worldwide. 


  • Version 1- In 1987; Synthesis was used as database for RADAR project.
  • Version 2- In April, 1988. (10.5 MB was released).
  • Version 3- In September, 1990. (11.5 MB was released). This version contains 136000 additions from 130 authors compared to Kent’s original repertory.
  • Version 4- In December, 1992. It contains 178000 additions from 200 authors.
  • Synthesis 5x- German edition was published in August, 1993. English edition was published in February, 1994. Indian edition in March, 1996. Dutch edition in April, 1994, with only ‘Mind’ chapter. This version was first time printed as book form.
  • Synthesis 6- German edition in August, 1995.
  • Synthesis 7.1- English edition in July, 1997. It contains 235000 additions from 330 different sources.
  • Synthesis 8.0- In February, 2002. It has 3031 author references and 4200 medicine references.
  • Synthesis 9.0- In November, 2003.
  • Synthesis 9.1- In June, 2004.

Synthesis treasure edition: The synthesis treasure edition was released as software in English and German on February, 2007. The French version was released in March, 2006. This edition is called treasure edition as the Synthesis repertory now includes Kent’s “Lost Treasure” — 11,398 additions and corrections that were noted by Kent in his personal copies of his Repertory, plus 333 handwritten additions taken from his copy of Hering’s Guiding Symptoms.

At each edition or version of Synthesis the quality has improved as it is quite evident from the data that there was a 24% increase in new information from Synthesis 2 to Synthesis 3, and there was a 30% increase in new information from Synthesis 3 to Synthesis 4. In Synthesis 4 software version (December 1992) contains 178,000 additions to Kent’s repertory from about 2,000 reliable sources. Publication of Synthesis 5 was a milestone as it was the first printed version. Synthesis shows a drastic increase in quality of repertory considering its structure, language and information. In further versions also synthesis went on improving its exclusive quality on the basis of maintaining following criteria:

  • By doing corrections in the basic repertories (Kent’s repertory) in a systematic manner.
  • Different persisting symptoms are edited in more comprehensive format.
  • Different words are modified by adding many new rubrics and new remedies after repeated verifications.
  • Adding synonyms and cross references.

It is based on the sixth American edition of Kent’s Repertory and contains all its rubrics and remedies. Therefore this repertory maintains the philosophy of Kent i.e. concept of individualization through evaluation of symptoms, evaluation of symptoms following deductive logic, gradation of medicine & it’s basis, cross references etc. This repertory is the best example of the expanded version of Kent’s Repertory from 1916 till date. It retains the hierarchical structure; therefore there is no need to learn a new format. 

1. Arrangements of different chapters like that of Kent’s Repertory i.e. chapters based on anatomical division with certain exceptions which are as follows-

  • 1st section is on Mind and the last one, Generalities.
  • Discharges, e.g. stool, sweat, expectoration and urine appear as separate sections next to the anatomical region producing them.
  • Certain general conditions, such as vertigo, cough, sleep, chill, and fever appear also as separate sections.
  • This repertory is divided into 38 chapters; Dream being new chapter.

(1)   Mind               (11) Teeth                    (21) Urethra                (31) Extremities

(2)   Vertigo            (12) Throat                  (22) Urine                    (32) Sleep

(3)   Head               (13) External Throat    (23) Male                     (33) Dream

(4)   Eye                  (14) Stomach               (24) Female                 (34) Chill

(5)   Vision              (15) Abdomen             (25) Larynx                 (35) Fever

(6)   Ear                   (16) Rectum                (26) Respiration          (36) Perspiration

(7)   Hearing           (17) Stool                    (27) Cough                  (37) Skin

(8)   Nose                (18) Bladder                (28) Expectoration      (38) Generals

(9)   Face                 (19) Kidney                 (29) Chest

(10) Mouth            (20) Prostate gland      (30) Back

2. General arrangement of rubrics in each chapter are like that of Kent’s Repertory which as follows-

  • Under each section rubrics run in alphabetical order.
  • Symptoms are divided in groups and these groups are always following each other in this same order
  1. SIDES
  2.  TIMES

This order of groups is repeated at each level if needed. We can expect a hierarchical structure like this at several levels-







TimeModalitiesExtension SideModalityExtension SideTimeModality- T/M/E


Modality Side- T/M/ETime-SModality-



Extension- M

At this point, if there is a chapter with a rubric pain, there is a ‘description of pain’-section. The whole table can be repeated, if the corresponding symptoms exist.

Note: ‘S’ stands for = Side; ‘T’ stands for = Time; ‘M’ stands for = Modality; ‘E’ stands for = Extension.

3. Gradation of medicines

BOLD CAPITAL 4 Marks 1st grade
Bold small 3 marks 2nd grade
Italics 2 marks 3rd grade
Ordinary roman 1 mark 4th grade

E.g. Jealousy

It is primarily and mainly based on the Kent’s Repertory. Other sources that were added are as follows:-

  1. Different authentic Repertories like Boger Boenninghausen’s Characteristic Repertory, O.E. Boericke’s Repertory, Phatak’s Repertory and others.
  2. Different Materia Medicas of some classical authors like Hahnemann, Kent’s Materia Medica, Hering’s Encyclopedia, Allen’s Encyclopedia, Robert’s “Sensation as if ”, other source books of Materia Medica e.g. Clarke’s dictionary, William Boericke’s Materia Medica, Phatak’s Materia Medica, Tyler’s Drug Picture etc.
  3. Some clinical observations from different authentic living authorities.
  4. New proving from reliable sources like Louis Klein, Jeremy Sherr and Nuala Eising etc.

Synthesis 9.1 version is the latest one and contains 2373 remedies.

In making this repertory more authentic and more up-to-date, Dr. Schroyens formulated and added the following plans and construction.

1. Addition after repeated checking Synthesis contains repeatedly checked additions from the standard homoeopathic literature including Dr. Hahnemann, Kent, Hering, Allen, Boericke, Knerr etc. Additions from other living authorities have been included only after proper verification.

2. Correction of Kent’s repertory These corrections are recognized by indicating ‘K’. E.g. Delusion – Starve he must – Kali.chl. Is corrected to Delusion – Starve he must – Kali.m.hr1,k,*. Here corrected source is Hering’s ‘Guiding symptoms of our Materia medica’. In this way thousands of corrections have been made.

3. Symptoms are re-written in clearly readable format Many symptoms are rewritten in proper readable symptom format. For better comprehension at each level the words follow each other in normal order or the symptom is split with indicating sign “ ” to show the place from which one should start reading. Example – “pieces, sensation as if head would fall in when stooping”. It is correctly written as “pieces, on stooping; sensation as if head would fall in”.

4. Combined modalities are applied throughout Synthesis, such as aggravation from ‘cold wet weather’ it would be searched as ‘weather-cold-wet’, but never under ‘cold-damp-weather’ and ‘damp-cold-weather’.

5. Clarification of ambiguous wordsAmbiguous words have been clarified wherever necessary. Example – ‘breast’ have been replaced by ‘mammae’ or ‘chest’ and ‘storm’ by ‘stormy weather’ or ‘thunderstorm’.

6. Creation of some rubrics – Some more important and useful rubrics are created so that more appropriateness of the meaning of the symptoms can be achieved such as ‘periodicity’, ‘children’.

7. Revision of language correction of some nineteenth century spelling have been corrected by modern American English spelling like

  •  Anaemia          =>        Anemia
  •  Diarrhoea        =>        Diarrhea
  •  Faeces             =>        Feces

8. All symptoms with ‘ailments from’ have been grouped in separate sub rubrics under the rubric ‘ailments from’.

9. Aversion, desire, aggravation, amelioration related to food are placed under rubric ‘food and drink’ in the chapter ‘Generals’.

10. Several clinical rubrics are renamedClinical conditions are renamed according to modern disease names e.g. ‘hay fever’ for ‘coryza – annual’, ‘decubitus’ for ‘skin become sore’.

11. All dreams are present in a separate chapter ‘Dream’ following ‘Sleep’.

12. Similar rubrics are merged into one, such as ‘nose-obstruction-alternating sides’ it is corrected into ‘nose-obstruction-one side alternately’.

13. Use of leading words Leading words have been placed in front of each level and the alphabetical sorting were corrected accordingly e.g. ‘in bed’ become ‘bed in’ and ‘as if frozen’ became ‘frozen as if’ etc.

14. Formation of complete and clear symptomsInsufficiently clear symptom became much more completed on  the basis of knowledge of materia medica e.g.- ‘cough- sulphur fumes or vapours sensation of agg’ becomes ‘cough- sulphur fumes  or vapour, cough agg. by sensation of’.

15. Use of more comprehensible wordsseldom used words have been replaced by contemporary words for better understanding e.g. ‘dypsomania’ became ‘alcoholism’; ‘childbed’ became ‘delivery after’.

16. New standard list of remedy abbreviationsA new standard list of remedy abbreviation is presented. Many new remedies have been added, all abbreviations of following the same rules used by Kent. The differences between abbreviations of Synthesis and those used so far in Kent or in Barthel’s Synthetic repertory are printed in the beginning of this book. The full list and all comments follow at the end.

17. New standard list of Author abbreviationsA new standard list of author abbreviations is presented as well. Letters are used to indicate an author. This allows more combinations and easier to memorize. No single addition has been made without indicating the source. One reference refers to only one author, if possible even to exactly one book or article, which makes it even easier to go back to the sources. The full list of reference is found at the end of this repertory.

18. Index of important changes and correctionsAll changes have been annotated with great care in order to allow verification. Thousands of references and synonyms have been incorporated where a change was made to well rubrics or remedies. When it was not possible to indicate the change, the correction was mentioned in the “index of important changes and corrections” which can be found in the end of this repertory.

Some special features of chapter ‘MIND’

  • More rubric and medicines are added in the chapter mind in comparison to Kent’s repertory.
  • About 529 rubrics are present in Kent’s repertory whereas in Synthesis it is 848.
  • The following rubrics are added in Mental chapters

Ailments from – anger

bad news


indignation etc.


Love for animals-


dogs : aeth.

–        pet; her: med, nat-m, podo.

children; in: med.

  • NATURE: love: care. Etc.
  • BEHAVIOUR Problems:

–          children in (destructiveness, disobedience, insolence, Restlessness, rudeness etc in children.)

  • BUSINESSMEN: worn – out businessmen; suited to: calc, coca, kali-p. Nux-v.

Passion for gambling:

Make money to:

Some special features of ‘GENERALS’ chapter

  • In Kent’s repertory there are 245 rubrics, in generals whereas in Synthesis it is 780.

The following exclusive rubrics are there:

–        FOOD & DRINKS: contains all desire, aversions, and modalities.

–        Few important rubrics are listed below-

Rubrics on pathological conditions / clinical conditions Acetonemia; Acidosis; Acromegaly; Adrenal failure; Agranulocytosis; Alzheimer’s disease; Amoebiasis; Amyotrophic lateral sclerosis; Arteriosclerosis, Down’s syndrome; Leukemia; Parkinson’s disease; Poliomyelitis; Polycythemia; Reiter’s Syndrome; Tuberculosis; Vericose veins etc.
Rubrics of poisoning / abuse of Of Aluminium; Arsenical; Mercury; Chemotheraphy; Psychotropic drugs; Quinine; Radium theraphy; X-Ray burn etc
Rubrics on laboratory findings Erythrocytes decreased; Leucocytes decreased, increased; Platelets decreased; Sperms count low etc.
Rubrics on vaccination after Diphtheria; DPT; Meningitis; Neurological complaints; Prophylaxis; Rabies etc.
Rubrics on children complaints Delicate; Punny; Sickly; Teenagers etc.
Rubrics on family history of Asthma; Cancer; Diabetes mellitus; Eczema; Gonorrhoea; Insanity; Suicidal death; Tuberculosis etc.
Rubrics on personal history Abortion; Antibiotic use of; Abscess recurrent of; Birth trauma of; Bite of animal; Gonorrhoea etc.
Rubrics on physical makeup Lean people; Obesity; Emaciation etc.
Rubrics on complexions Dark; Fair etc.
Rubric on moon phases Full moon; New moon; Waning moon; Waxing moon etc.
Rubrics on periodicity like Day – Alternate day; 4th day; 10th day; Hour; Week; Month; Year etc.

 Few important rubrics with corresponding drug (s) from chapter ‘Generals’

Acetonemia: carb-ac Acromegaly: carc, Pitu, thyr
Adrenal failure: p-benzq Agranulocytosis: chloram, cortico, lach, sulfa
Alzheimer’s disease: alum, cordyc, hell, nux-m Amebiasis: emetin
Aspirin, from: mag-p Blood: affection of the- arn
Camphor: from- carb-v Chloroform; ailments from: acet-ac, phos
Chamomile: desire for- gink-b Chronic diseases, to begin treatment: calc, calc-p, morb, Nux-v, psor, puls, Sulph, tub
Collagen diseases: des-ac, penic, saroth, suis-chord-umb Cryptococcosis: cryptc
Cushing’s syndrome: cortico, cortiso Disabled: congenital- syph
Down’s syndrome: morg-p, pert, toxo Dystonia; autonomic: adren, tetrac
Embolism: kali-m Eosinophilia: brass-n-o
Family history of: anemia, measles, mumps, typhoid fever, ulcers on stomach- carc Hypotony: atra, gels
Infectious disease: acon, bell, cortiso, echi, nat-ox-act Iodine deficiency symptoms: calc-i, fuc, sil, spong, thyr
Lepra: accompanied by clean tongue- agar Leukocytosis: cloth, loxo-recl, tub
Many symptoms: agar, Carc, Tub Menthol: from- carb-v
Mining, ailments from: card-m, nat-ar, sulph Myasthenia gravis: cur, cytin, gels, nat-m, pic-ac, sulph
Myopathia: alum, germ-met Myxedema: Ars, cortico, dor, penic, prim-o, sulfa, Thyr
Ossification: arteries, of- lith Polycythemia: cean, lach
Radium treatments, from: cadm-met, caust, rad-br Reiter’s syndrome: Med
Sewer-gas poisoning: anthraci, Bapt, phyt, pyrog, Tub Shock; anaphylactic: ant-t, apis, Carb-ac, tetox
Silica; from overdose of: camph, Fl-ac, hep, merc, sulph Sjogren’s syndrome: nux-m, tub, tub-m
Tetanus: anac, anag, cocc, cortico, hyper, ip, scor-          Prophylaxis: Arn, hell, Hyper, lat-m, Led, scor, tetox, thebin, thuj Torpor of the left side of body: acon
X-ray burn or treatment; after: cadm-met, fl-ac


  1. This repertory is based on Kentian philosophy, so very easy to use as most of us quite acquainted with Kent’s repertory through its frequent use.
  2. Plan and construction is planned according to Hahnemannian schema. So, it is quite easy to search the required rubric.
  3. More medicines are there in synthesis repertory than previous repertories.
  4. New rubrics being added, old rubrics and their corresponding medicines are verified & upgraded where required.
  5. All materials are collected from reliable sources and for every new addition references are provided. So this repertory is one among the authentic repertories.
  6. Rich in cross references.
  7. Method of repertorization follows the Kent’s method of repertorization.
  8. Constant update is going on to make this repertory perfect day by day.
  9. Standard format is formed while constructing this repertory.
  10. New proving is being incorporated.
  11. New rubrics are created as in chapter of ‘Generals’- rubrics on different pathological conditions, poisoning, complexions, children complaints, physical makeup, vaccination after, laboratory findings etc. These rubrics are of immense value in present day practice and they are the gems of this repertory.
  12. Rubrics on moon phases, periodicity, family history, personal history are the unique creation of this repertory.

Any case rich in generals and characteristic particular can be repertorized by Synthesis. A case having only characteristic particular too can be repertorized by using this repertory. Now it is so elaborated in each chapter any type of totality can be worked out with this repertory.

We mostly depend upon Kent, BTPB, BBCR as we are all conversant with these books through their frequent use and also they have strong philosophical background. These new repertories mention about the sources from where they have been taken. In contrary, Kent has taken much information from different sources in his repertory, but he did not mention anything about the source. He even had not considered many works which remain untouched. These new repertories are of immense value and have done great benefit to the profession. Synthesis Repertory is one among the modern repertories. New rubrics being added, old rubrics and their corresponding medicines are verified & upgraded where required. New medicines are added.

So far no drawbacks as this repertory is constantly being updating and correcting the materials except about the reliability of new additions of living authors.


  1. Das AK. Fundamentals of Homoeopathic Repertory. 1st published in 2003. Souvik Homoeo Publications. Calcutta; 2003.
  2. Dev AT. Student’s Favourite Dictionary. 25th edition. Published by A. C. Majumder. Calcutta; 1994.
  3. http://www.merriam-webster.com/dictionary/synthesis
  4. http://www.wholehealthnow.com/homeopathy_pro/frederik_schroyens.html
  5. http://www.wholehealthnow.com/homeopathy_software/radar105.html
  6. PV S. A Reference to Repertories for Homoeopathic Students. 1st edition. B. Jain Publishers (P) Ltd. New Delhi; 2007.
  7. Rastogi DP. An Overview of Repertories. 2nd edition. B. Jain Publishers (P) Ltd. New Delhi; 2008.
  8. Schroyens F. Synthesis (Repertorium Homoeopathicum Syntheticum). Version 7.1. Published in India by arrangement with Homoeopathic Book Publishers, UK by B. Jain Publishers (P) Ltd. New Delhi; 1998.
  9. Schroyens F. Synthesis (Repertorium Homoeopathicum Syntheticum). Version 8.1. Published in India by arrangement with Homoeopathic Book Publishers, UK by B. Jain Publishers (P) Ltd. New Delhi; 2001.
  10. Tiwari SK. Essentials of Repertorization. 4th edition. B. Jain Publishers (P) Ltd. New Delhi; 2005. 

Dr. Abhijit Chakma, MD (Hom.)
Senior Research Fellow (H), Clinical Research Unit for Homoeopathy,
¼ Main Road, Colonel Chowmuhani, Krishnanagar, Agartala-799001
E-mail- dr.abhijit24@gmail.com

*Senior Research Fellow (H), Clinical Research Unit for Homoeopathy, Agartala.
1This article is originally published by the same author in Bulletin of The National Institute of Homoeopathy (ISSN 0972-6276) Vol-15 No. 2 April 2012 (Page 57-63).

Removing the Limitations of Current Homeopathic Software – Schroyens

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