Homeopathic proving symptoms: result of a local, non-local, or placebo process? A blinded, placebo-controlled pilot study

Homeopathy. 2004 Oct;93(4):179-85. doi: 10.1016/j.homp.2004.07.006.


Background: Homeopathic pathogenetic trials (HPTs) (provings) are the pillar of homeopathy. Symptoms experienced by healthy volunteers are used to find the correct medicine for therapy. It is unclear whether these symptoms are specific or due to placebo noise. Furthermore, it is uncertain whether proving effects, if present at all, are due to a local or non-local process

Objectives: To develop a test model which allows for testing if homeopathic proving symptoms are caused by placebo or causative mechanisms, and if these symptoms are due to local or non-local processes.

Design: Randomised, blinded, placebo-controlled, parallel-group study, with 1-week baseline and 2-weeks proving period.

Subjects: 11 healthy volunteers from two different homeopathic schools. PROVING SUBSTANCE: An homeopathic medicine (Cantharis 30c), blindly chosen from 12 potential medicines, compared to placebo.

Outcome measure: Number of symptoms typical for the medicine in the experimental and control group during baseline and proving period.

Results: During baseline there was no difference in the number of typical or atypical symptoms in either group. During the proving period, both more typical symptoms for Cantharis (P= 0.03) and more atypical symptoms (P= 0.02) were observed compared to baseline. Between-group differences were not significant. Effect sizes for the difference between the proving and control group for typical symptoms was d=0.4, and for atypical symptoms d=0.6.

Discussion: This proving model could be valuable in studying the validity of proving symptoms of homeopathic substances in healthy volunteers.

Conclusion: Homeopathic proving symptoms appear to be specific to the medicine and do not seem to be due to a local process. Since this was a pilot study using a small number of provers, rival hypotheses cannot be ruled out and the study needs replication.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Homeopathy / methods*
  • Humans
  • Materia Medica / administration & dosage*
  • Materia Medica / pharmacology*
  • Pilot Projects
  • Placebo Effect
  • Reference Values
  • Surveys and Questionnaires
  • Time Factors


  • Materia Medica