Scientific proving of ultra high dilutions on humans

Homeopathy. 2015 Oct;104(4):322-7. doi: 10.1016/j.homp.2015.08.008. Epub 2015 Oct 12.


Background: Homeopathic drug provings or pathogenetic trials (HPTs) are the pillar of homeopathy. This review summarizes the authors' findings and interpretations derived from a series of homeopathic drug proving between 1994 and 2015. It gives an overview over a series of attempts to use modern scientific experimental methodology to answer the question, whether such HPTs produce symptoms in healthy volunteers that can be distinguished from placebo symptoms.

Methods: Various experimental models were used: repeated crossover trials with categorical data collection, and a single-case, randomised study. Final models use diligent qualitative data-collection in experienced volunteers. In those, raters decide whether symptoms are typical for a remedy delivered or not. The design is triple-blind and placebo-controlled.

Result: While previous attempts were inconclusive, this new model allowed to separate placebo symptoms from verum symptoms repeatedly in a series of two definitive studies following promising pilot studies. Results were statistically significant. Also, some signs of the purported non-local signature of homeopathic effects were visible, and the consequences for future methodology is discussed.

Conclusion: Provided some cautionary notes are taken into account, HPTs can be used to separate out true specific symptoms from placebo symptoms. By the same token this is a road to experimental proof that homeopathic remedies are not just placebos. However, this needs to be taken forward by independent groups.

Keywords: Double blind experimental studies; High dilutions; Homeopathy; Pathogenetic trials; Remedy provings.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cross-Over Studies
  • Double-Blind Method
  • Homeopathy / methods*
  • Humans
  • Indicator Dilution Techniques
  • Materia Medica / therapeutic use*
  • Pilot Projects
  • Placebo Effect


  • Materia Medica