Homeopathic research has developed over the past 20 years with the increasingly greater use of modern medical methods (clinical trials, observational studies, statistical evaluations, computerized storage programs and instrumental or laboratory testing). Over 200 clinical trials designed to verify the efficacy of homeopathic treatments have been published, many (but not all) of which have led to positive results. As in other medical disciplines, statistically significant results could be reached by pooling all of the methodologically reliable studies in a given area, but with homeopathy this occurred very rarely, because few series have been conducted for single conditions and because the experimental approaches or the medicines used are too heterogeneous to be able to conclude that any one protocol is efficacious. Some of these series document clinically useful effects and differences against placebo (1
) and some series do not (6
), or their evidence is ‘promising’ but insufficient for drawing conclusions (7
Recent controversies on the question of whether homeopathy is a placebo response (9
) have shown that an approved answer to this dilemma is at present not possible, because evaluation of the evidence and the inclusion or exclusion of papers from meta-analyses vary according to pre-selected criteria, that differ in different reviews, a sort of ‘bias’ of the observer (14
). Moreover, there is a noteworthy confusion concerning what type of ‘homeopathy’ is evaluated (e.g. use of low or high potencies) and when homeopathy is accused for its lack of ‘plausibility’ (9
), the different modalities are not suitably distinguished.
The aim of this lecture series is not to provide a meta-analysis of homeopathic literature, neither to focus on the placebo question, themes that have been addressed with variable results by others (1
), but to provide an overview of the best of available homeopathic literature in the fields of immunoallergology and common inflammatory diseases. As we have seen in the introductory lecture (27
), immunoallergology represents a bridge between homeopathy and modern medicine insofar as it is a field in which it is easier to apply concepts such as the effect of substances administered on the basis of the logic of the ‘similar’ and the great sensitivity of living systems to modulations induced by ultramicrodoses of natural or endogenous substances. In this field, there is a body of pre-clinical research suggesting that homeopathic remedies may regulate the immune system at cellular and/or systemic levels (28
). There are also preliminary ex vivo
observations of significant changes of immune cells (CD4 lymphocytes) in people treated with high potencies of homeopathic medicines (31
) and, broadly speaking, it has been suggested that T cells can be the target of immunoregulation by a range of complementary and alternative medicines (32
Patients with diseases of the immune system like allergies and asthma, or with enhanced susceptibility to recurrent infections, or with rheumatological diseases often have recourse to homeopathy as ‘alternative’ medicine (33
). Unfortunately, there is paucity of evidence-based recommendations using homeopathic remedies in these conditions.
Evidence-based medicine will have increasing impact also in the field of complementary and alternative medicine, but the systematic evaluation of research evidence in homeopathy is an expectation that requires suitable methods of evaluation (42
). In this new and controversial field, stringency of tools utilized to systematically evaluate the scientific literature should always be accompanied by a consensus concerning clinical protocols that significantly reflect modalities of cure, types of follow-up and relevance of outcomes, which can be different from those of conventional medicine. Otherwise the results, instead of helping the judicious use of evidence in making clinical decisions, become only the source of new controversy, especially when disseminated by the media, as was in the recent Lancet
's meta-analysis that was inappropriately boosted by the editorial title ‘The end of homeopathy’(44
Here, we have distinguished publications in two major groups, each of which holds a rationale for deployment of homeopathic remedies. A first group (described in this part of the review) includes pathologies consisting of anomalous susceptibility to infections that may be, at least in part, due to inadequacy of efficiency of the immune system in the rejection of an extraneous aggressor. The second group (described in a subsequent part of the review), includes pathologies due to hypersensitivity of the immune system, the most widespread of which is immediate hypersensitivity, or allergy, and its major manifestations at the level of respiratory system. For each group of pathologies, the different homeopathic methods utilized, namely (i) classical individualized homeopathy, (ii) isotherapy, (iii) specific medicines for each disease or symptom (pluralist or clinical approach) or (iv) complex formulations (used particularly in homotoxicology) are dealt with in separately. A general discussion of the evidence-based homeopathy in these fields will be reported in the second part of the review.