Adverse effects reported in clinical trials were mild and transient (mostly headaches, tiredness, skin eruptions, dizziness, diarrhoea or loose stools and aggravations of symptoms). These are common symptoms which often also occur with placebo, and the association with homeopathic treatment was generally judged 'possible'. Only in three (of 19) case reports were adverse effects judged as probably attributable to homeopathic medicines. Of these, two described aggravation of symptoms in individual patients, the other was a report of adverse effects from a homeopathic preparation also containing plant extracts not specified in the report. Many different homeopathic medicines and dilutions were mentioned in the reports.

The authors comment that the quality of the reports was generally poor, and sometimes confused homeopathic and herbal preparations. The issue of direct (due to the medicine per se) and indirect (due to the prescriber, rather than the medicine itself) adverse effects, is of considerable importance and merits further investigation. There appears to be under-reporting of adverse effects of homeopathy in the literature, perhaps due to a belief that homeopathy cannot do harm.⁴

However, there have been claims that homeopathic therapies do have side-effects, some of them dangerous. Indeed, one health authority put forward this argument as one of its reasons for purchasing homeopathy only in exceptional circumstances.

A briefing document from Lambeth, Southwark and Lewisham HA maintains that not only is homeopathy clinically ineffective but it is not as safe as adherents claim. "Many homeopathic preparations contain heavy metals, e.g. mercury, which, although diluted, can produce toxic symptoms in occasional cases", it says, and "anaphylaxis can also occur rarely, especially when injections are used" ⁵.

Such statements are untrue, according to the RLHH. Its medical and research director, Peter Fisher, says that the hospital has looked carefully at the world literature on the subject. Leaving aside cases of mistaken identity (that is where the medicine was herbal not homeopathic) and cases of malpractice, in which homeopathy was only incidentally involved, there are fewer than 10 reports of adverse side-effects.

As to heavy metal poisonings or anaphylaxis due to homeopathic medicines, Dr Fisher says he is not aware of a single case. Any purchaser making such a claim should be asked to produce the evidence.

Other safety concerns which can arise are i.) immunisation and ii.) the unregulated practice of homoeopathy by non-medical homeopaths.

1. Immunisation
   
   The policy of the Faculty of Homeopathy is to advise that children should be immunised according to the guidelines published by the Department of Health, provided there are no medical contra-indications.
   
   
2. Homeopathic practice by non-medical homeopaths
   
   Referral and delegation
   
   Because non-medically qualified homeopaths (NMQPs) are not statutorily registered, doctors and other statutorily registered health professionals cannot refer their patients to them, but only delegate care.

This means that the doctor retains at least some of the responsibility for the patient's treatment. In the case of referral, the health professional to whom the patient has been referred assumes responsibility for any treatment s/he may give. In the case of delegation to an NMQP, the referring doctor should have some personal knowledge of the practitioner and continue to monitor the patient while s/he is receiving treatment.