Is there enough evidence in favour of homeopathy for it to be used for ADHD, asthma, or dementia? The best way to find out is probably to conduct a systematic review. Fortunately, someone has already done this for each of these conditions – and for others.
In December last year, I commented on a discussion on the Think Humanism Forum. It had been pointed out by an advocate of homeopathy that “Studies in support of Homeopathy have been published in […] journals” and a list followed. One of the items listed was “Cochrane”, so I thought I’d take a little look at Cochrane Reviews of Homeopathy.
I used “homeopathy” as a search term on Google, limiting the search to the Cochrane website, and posted from the plain language summary of each review.The first page of Google results contained 10 results, and 5 of these were reviews.
One Homeopathic remedies (potencies) aim to minimise the risk of adverse effects. There are different types that may be used for asthma, such as classical homeopathy (tailored to an individual’s symptoms) or isopathy (for example using a dilution of an agent that causes an allergy, such as pollen). The review of trials found that the type of homeopathy varied between the studies, that the study designs used in the trials were varied and that no strong evidence existed that usual forms of homeopathy for asthma are effective. There has been only a limited attempt to measure a ‘package of care’ effect (i.e., the effect of the medication as well as the consultation, which is considered a vital part of individualised homeopathic practice). Until stronger evidence exists for the use of homeopathy in the treatment of asthma, we are unable to make recommendations about homeopathic treatment.
It looks to me as if claims that homeopathy can be used to “treat”, “help with”, or “cure” asthma are unfounded and inappropriate.
Two Dementia is a distressing illness that has major implications for individuals with the disease and their carers. Homeopathy is a popular type of complementary medicine. It is however controversial because although there is some evidence that it is not just a placebo, no one understands how it could work. The researchers did not find any good quality trials and so cannot say whether it is or is not effective for treating this condition. As no information is available on how much homeopathy is used for dementia, it is difficult to say whether it is important to conduct more trials.
The researchers did not find any good quality trials studying homeopathy for dementia. Why, if this is the case, can I find homeopathic remedies for dementia that are available on the internet? Some are even listed by the University of Maryland Medical Center website.
Three This review aimed to assess the evidence for homeopathy as an intervention for attention deficit/hyperactivity disorder. Four trials were retrieved and assessed with mixed results. Overall the results of this review found no evidence of effectiveness for homeopathy for the global symptoms, core symptoms or related outcomes of attention deficit/hyperactivity disorder.
Another Cochrane review, another strike. I make that three now – if this were Baseball, it would now be game over for homeopathy. No evidence of effectiveness for homeopathy. It doesn’t get much clearer than that.
Four This review looked at whether these [homeopathic] medicines could help patients with problems caused by cancer treatments […] Two studies with low risk of bias demonstrated benefit: one with 254 participants demonstrated benefits from calendula ointment in the prevention of radiotherapy-induced dermatitis, and another with 32 participants demonstrated benefits from Traumeel S (a complex homeopathic medicine) […] These trials need replicating. Two other studies reported positive results, although the risk of bias was unclear, and four further studies reported negative results. […].
Eight studies. Only two studies with low risk of bias showed benefit. Two further studies that weren’t well-designed enough to be reliable showed benefit. Four studies were negative.
Five The review of trials found there was not enough evidence to show the effect of a homoeopathy as a method of induction. More research is needed.
The first review found no strong evidence in favour of homeopathy for asthma. The second review couldn’t find a single good quality trial – perhaps this should be seen as an indictment of homeopathic research, or perhaps it should be seen as an indictment of those who promote homeopathy for dementia. The third review found no evidence of effectiveness of homeopathy for ADHD.
One review found two of eight trials showing benefit, two trials where bias was unclear and four trials that were negative. To me, this seemed the most positive review – yet only half of the trials showed benefit and of those trials only half had a low risk of bias.
The final trial found insufficient evidence to recommend the use of homoeopathy as a method of induction.
If any medical (or pseudomedical) practitioner wishes to recommend homeopathy for ADHD, asthma, induction of labour, dementia, or side-effects of cancer treatments then I think that they should first provide good evidence that their choice of treatment is effective.
The same applies to any manufacturer or vendor of homeopathic remedies. If they produce or sell a remedy that is for a specific condition, they should show us the evidence of efficacy.
Note for commenters: posting single studies to ‘prove’ homeopathy works in response to this post will not trump the evidence from systematic reviews. The responses to your ‘proof’ might be quite entertaining though, so please do feel free to post your cherry-picked research should you wish to do so.