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Good medicine: homeopathy

BMJ 2012; 345 doi: (Published 14 September 2012) Cite this as: BMJ 2012;345:e6184

Re: Good medicine: homeopathy

Christopher Johnson asserts that critics of homeopathy show “true love of mediocrity, conformism and brain-dead enforcement of orthodoxy (dogma) […] that would make an Inquisitor blush."

I dispute this. Critics generally understand homeopathy well, albeit not as homeopaths would see it.

Mr Johnson says the "criticism of homeopathy as 'unscientific'" is "not based on any hard evidence", but many reviews of the science exist, most notably the UK's House Science and Technology Committee Evidence Check. [11] Sir Mark Walport, Chief Scientific Advisor to the UK Government, says: "My view scientifically is absolutely clear: homoeopathy is nonsense, it is non-science."[1]

Mr. Johnson says: "The fact is, the weight of the evidence strongly favors homeopathic remedies being biological active agents." This is simply wrong. Linde et. al.[2] and Shang et. al.[3] both surveyed the literature and concluded that it offers no credible evidence of effect beyond placebo, and that weaker and more biased studies are more likely to be positive while more robust studies are more likely to be negative.

There is no debate over whether pharmaceuticals can materially influence body chemistry. The existence at this late stage of a dispute as fundamental as this over homeopathy shows that, contrary to his assertion, the science clearly is not behind him. A systematic review of systematic reviews [5] found:

Collectively [reviews] failed to provide strong evidence
in favour of homeopathy. In particular, there was no
condition which responds convincingly better to
homeopathic treatment than to placebo or other
control interventions. Similarly, there was no
homeopathic remedy that was demonstrated to yield
clinical effects that are convincingly different from
placebo. It is concluded that the best clinical
evidence for homeopathy available to date does
not warrant positive recommendations for its use in
clinical practice.

Attempted demonstrations of mechanisms supportive of homeopathy turn out to be either fatally flawed [5] or irreproducible [6]. Homeopathy lacks consilient findings; in fact relevant science generally contradicts it supportive effects seem only to be found by believers actively seeking them.

Homeopathy apologists apply a selective approach, asserting individual results as supporting parts of homeopathy but never addressing the full necessary chain of action: [7]

1. Disease is caused by miasms which disturb the vital force within the body.
2. "Like cures like", that is, a substance which causes a certain symptom at pharmacological doses will, diluted, cure a disease that produces that symptom.
3. Each individual is unique and the remedy required will depend on the constitution of the individual (choleric, sanguine etc.).
4. The healing energy of the remedy is dynamised and potentised by serial dilution and succussion (striking on a resilient surface).
5. The energy becomes more potent with increasing dilution.
6. The energy can be transferred to an intermediate such as a sugar globule by dropping the dilute remedy on the globule and allowing it to evaporate.
7. The energy can then be transferred to the body via that medium.
8. The remedy may then cure the disease, make it worse (induce a healing crisis), or fail, in which case the wrong remedy was chosen and another should be tried.

I must admit to being mildly cynical of these claims. The last, in particular, seems to be an escape clause which permits any result as a validation of homeopathy.

Miasms? Long since discarded. Vital force? Never measured by any scientific instrument, appears to violate laws of conservation of energy and thermodynamics. Like cures like? Not a generally useful property of medicine. Each individual is unique? Not so much; gene therapy for certain cancers is promising but most diseases exploit similarities between individuals not differences - a streptococcus is a streptococcus is a streptococcus.

It is important to recognise that there is disagreement among homeopaths over "imponderable" remedies; "clinical homeopathy" versus “classical”; isopathy; disagreement over the number of strikes and force required during succussion (or even, for some, whether it's necessary at all); the Korsakovian method.
And this comes direct to Mr. Johnson's point about science. If such disputes existed in medicine, they would be resolved by experiment and/or clinical trial. In homeopathy, few if any of the purported effects are objectively measurable and experiments are almost universally ambiguous. Disputes are resolved by appeal to interpretation of authority, by schism, or by simply ignoring them.

That is not science. That is philosophy. Religion, even.

The ideas of potentisation, dynamisation, and transferability present the biggest problems. No figures exist for the reported energy, or force required to impart it and ordered structures in liquid suggested as a mechanism of transfer have a duration measured in femtoseconds. Can the energy transfer from water to sugar? I do not see why this would be the case: the approximate molecular mass of water is 18 g/mol, of lactose 342 g/mol. There’s no reason to suppose these molecules would behave in a similar way, and why is succussion not required to transfer the "energy" to the sugar globules?

I do not think that arm-waving appeals to a subtle energy never measured or quantified, can be defended.
How do we account for the difference between the scientific consensus and Mr. Johnson’s interpretation?

There is a clue in the sources he cites:
• Homeopathy. 2007 Jul;96(3):175-82.
• Homeopathy. 2010 Oct;99(4):231-42.
• Homeopathy. 2007 Jul;96(3):163-9.
• Complement Ther Med. 2007 Jun;15(2):128-38. Epub 2007 Mar 28.
• J Clin Psychiatry. 2011 Jun;72(6):795-805. doi: 10.4088/JCP.10r06580.
• J Clin Epidemiol. 2008 Dec;61(12):1197-204. doi: 10.1016/j.jclinepi.2008.06.015. Epub 2008 Oct 1.
• Homeopathy. 2008 Oct;97(4):169-77. doi: 10.1016/j.homp.2008.09.008.
• J Clin Epidemiol. 2008 Dec;61(12):1197-204. doi: 10.1016/j.jclinepi.2008.06.015. Epub 2008 Oct 1.
• Homeopathy. 2008 Oct;97(4):169-77. doi: 10.1016/j.homp.2008.09.008.

One journal is homeopathy specific. Others studies appear in journals whose peer reviewers may not be well qualified to understand the problematic assumptions which underlie them. Barrett has discussed exactly this issue and notes that "respectable journals have done a remarkably poor job of screening out low-quality "CAM" manuscripts"[8].

It is certainly inappropriate to dismiss out of hand the expression of the scientific consensus by Sir Mark Walport [1], Professor Sir John Beddington [9] and Professor Dame Sally Davies [10].

[1] Homeopathy is nonsense, says new Chief Scientist, Daily Telegraph, 18 April 2013.
[2] Linde, K; Scholz, M; Ramirez, G; Clausius, N; Melchart, D; Jonas, WB (1999), "Impact of Study Quality on Outcome in Placebo-Controlled Trials of Homeopathy", Journal of Clinical Epidemiology 52 (7): 631–6
[3] Shang, Aijing; Huwiler-Müntener, Karin; Nartey, Linda; Jüni, Peter; Dörig, Stephan; Sterne, Jonathan AC; Pewsner, Daniel; Egger, Matthias (2005), "Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy", The Lancet 366 (9487): 726–732
[4] Ernst, E. (2002), "A systematic review of systematic reviews of homeopathy", British Journal of Clinical Pharmacology 54 (6): 577–82
[5] Maddox, J.; Randi, J.; Stewart, W. (1988). ""High-dilution" experiments a delusion.". Nature 334 (6180): 287–291.
[6] Homeopathy: The Test, BBC, 26 November 2002
[7] Homeopathy: How It Really Works, Shelton, Jay ISBN 159102109X
[8] Problems with "CAM" Peer-Review and Accreditation Barrett, S
[9] Homeopathy on the NHS is 'mad' says outgoing scientific adviser, Daily Telegraph, 9 April 2013
[10] Homeopathy is 'rubbish', says chief medical officer, Daily Telegraph, 24 Jan 2013
[11] House of Commons Science and Technology Committee Evidence Check 2: Homeopathy, HMSO, 22 Feb 2010

Competing interests: No competing interests

05 May 2013
Guy Chapman