Thursday, 3 June 2010

Homeopathy 101.

This is Part II of a run of posts about homeopathy. Here's Part I, which is really just an intro and will become an index to the other posts as they become available. This post is a primer in the history and theory of homeopathy, which I will try to without too much criticism. The debunking will follow in subsequent posts.

One common claim of those who endorse homeopathy, although rarely by practitioners, is that it has been in use for thousands of years and therefore must be effective. There are two things wrong with this statement: the first is that it is a shining example of the Appeal to Tradition, a logical fallacy exemplified by the fact that is plainly possible (née likely) for our ancestors to be wrong about many things for a very long time; longevity is no guarantee of veracity. The other objection is that not only would the claim be invalid if the statement were true, but also that it is just plain false. Homeopathy is not part of some ancient tradition or folk-wisdom; it was invented in Germany in 1796.
Samuel Hahnemann (1755-1843), a German physician, became understandably disillusioned with the state of 18th century medicine; claiming, quite rightly, that it often did more harm than good. Double-blinded, randomised, controlled (placebo or otherwise) trials would not come into standard use for many years yet, so no reliable mechanism of testing treatments was available; the germ-theory of disease was not yet completely synthesised and its budding principles were not accepted by most. Medicines with unknown effects were often administered to patients with unknown diseases with little idea of the consequences. Bleeding, the practice of draining people's blood, was still the favoured technique for many conditions; this frequently killed patients who would otherwise have survived without intervention, and accelerated the demise of many others. Early medicine was so fraught with problems that it caused Hahnemann to retire from practice to focus on writing and translation. He later explained why thus:
My sense of duty would not easily allow me to treat the unknown pathological state of my suffering brethren with these unknown medicines. The thought of becoming in this way a murderer or malefactor towards the life of my fellow human beings was most terrible to me, so terrible and disturbing that I wholly gave up my practice in the first years of my married life and occupied myself solely with chemistry and writing.
I think this passage illustrates to some degree that the scorn heaped upon poor old Sam is unjust; he was clearly a man who wanted to help but rightly felt that medicine did not have the tools to enable him to do so. He also obviously had an eye for when he was harming more than helping.

Some while after his retirement from medicine, while translating William Cullen's Materia Medica into German, Hahnemann encountered a claim that cinchona bark, from which the anti-malarial quinine was later isolated, worked against malarial fevers due to astringent properties acting as a "tonic to the stomach"; a claim of which he was sceptical1, and during his investigations decided to experiment on himself. Shortly after taking his first dose he experienced symptoms that he described as "ordinarily characteristic of intermittent fever", and repeated doses had a similar effect. This lead him to the following reasoning: If a substance that can relieve a disorder causes the symptoms of that disorder in a healthy person, then it is also true that other substances that causes symptoms in a healthy person, will cure diseases that have similar symptoms2. Our Sam calls this principle Similia Similibus Curentur (like cures like), while modern homeopaths sometimes refer to the "law of similars". He writes:  
The curative power of medicines, therefore, depends on their symptoms, similar to the disease but superior to it in strength, so that each individual case of disease is most surely, radically, rapidly and permanently annihilated and removed only by a medicine capable of producing (in the human system) in the most similar and complete manner the totality of its symptoms, which at the same time are stronger than the disease.
Calling his new system of treatment "homeopathy", from the Greek for "Similar Feeling", or "Similar Disease" he then embarked on a series of experiments he called "Provings", so named from "Prüfung", the German for "Test". These experiments consisted of taking groups of healthy individuals and administering a substance purported to have some effect on the body of a period of time and recording any symptoms suffered by the subjects.
There is no other possible way of correctly ascertaining the characteristic action of medicines on human health, no single surer, more natural way, than administering individual medicines experimentally to healthy people in moderate doses...3
The symptoms experienced by these subjects were meticulously noted and studied after the experiments to determine what the substance would purportedly cure. In this manner, Hahnemann assembled his own Materia Medica, laying the foundation for those still in use by homeopaths today.
When administering his new found cures to patients, he discovered that some suffered from complications and unpleasant side effects from the remedies. He found that diluting the base remedy ameliorated the side effects, and eliminated them after sufficient dilution had occurred. Remarkably, the more dilute the solution, the faster the patient's recovery. This lead him to another principle of homeopathy: that dilution actually makes the curative powers of the base substance grow; that it is, somewhat counter-intuitively made more potent by the dilution process. This is often referred to as the "law of infinitesimals". The process followed is to drop 1 part of the active ingredient (or mother-tincture) into either 10 or 100 parts of water, and then take 1 part of the resultant solution and put that in 10 or 100 parts of water, repeating until the desired potency is reached. The nomenclature for the potencies is 1X for 1 part in 10, or 1C for 1 part in 100. 2C does not mean 2 parts per 100, but rather 1 part in 100 in 100 or 1 in 10,000. Today remedies are commonly between 10C (1 part in 100,000,000,000,000,000,000) and 30C ( 1 part in 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000), although mother-tinctures and potencies up to 1000C (such as carcinosin, a nosode4 made from cancerous cells and purported to cure cancer5) are available. Modern science has taught us that at dilution beyond 12C there virtually no chance of their being a single molecule of the mother tincture in a litre of water, at 30C to have a reasonable chance of getting a single molecule you would need a sphere of water the same diameter as the distance from here to the sun, and at 100C you would need around twelve times more molecules  of water than there are atoms in the entire observable universe to expect to see a single one of the original substance with any certainty. Homeopaths tell us that these absurdly large numbers are irrelevant, and that the water somehow retains a "memory" of the original substance, or that the physical structure or arrangement of the H2O is altered by the presence of the substance, and it is this memory that can effect cures to diseases. This memory is ostensibly aided by another principle of homeopathy that we shall come to next.
At some point during the formulation of the principle of dilution, Hahnemann hit on the idea of "succussion". Succussion is a process whereby the bottle containing the solution is struck firmly a number of times on a firm but elastic body which, Hahnemann said, increased the potency of the remedies. Some have suggested that he hit upon this idea after transporting some of his remedies on horseback, and later found these remedies to be of greater effectiveness. This is hotly disputed amongst homeopaths, and there is nothing directly referring to the discovery in his writings. We do however know two things that are pertinent to this. The first is that the "elastic surface" against which Hahnemann struck his phials of solution was a pad made of leather and stuffed with horsehair, which he  had specially commissioned from a saddler. The second is that his writings cautioned against taking remedies on long journeys because the remedy "receives an enormous number of additional succussions during the transport, and they are so highly potentized during a long journey, that on their arrival they are scarcely fit for use"[ref]. Whatever the origin, modern homeopaths claim that the succussion is integral to transferring the potency of the original ingredient to the water; that the knocking causes the water to somehow pick-up or resonate with the energy6 of the solute; this memory remains, and in fact strengthens, long after there ceases to be even the tiniest part of the solute remaining in the solvent. Hahnemann even claimed that after a period of rest, a remedy could be shaken to reinvigorate its powers. Luckily, when the remedy is in pill form, no amount of extra transport succussion will render the the remedies any more unfit for use than they were when they left the factory.

What's that? Pill form you say? Yes, although Hahnemann did make solid matter into remedies by grinding them down with lactose, this is rare today. Many modern homeopathic remedies come in the form of vials of "pillules". Pillules are tiny balls of sugar, onto which has been dropped some water from the diluted remedy, which are then allowed to dry out. I haven't actually heard any homeopaths explain how this is meant to work. Presumably the sugar retains the memory of the memory of water? Whatever the mechanism of action, it is apparently imperative for the effectiveness of the pillules that they do not come into contact with the hands, as the acids or other impurities on the skin are alleged to inhibit the remedy.

Hahnemann's theory of diesease, is that disorders are caused by something called Miasms, which are often described as a "peculiar morbid derangement of vital force". He also claims that allopathy7 fails because it treats only the symptoms of the disease, while failing to address the miasms that are the root cause. Homeopathic remedies however are believed to go deeper and address these miasms directly. It is this belief that causes many homeopaths today to continue using phrases like "it treats the disease not just the symptoms".

And that's just about it. More than any non-homeopath ever needs to know about the principles and practice of homeopathy except for one small thing: it just doesn't work. And it's mechanism of action is implausible. OK two things. Oh and there is no scientific evidence for any of its principles. OK three things. And there is no good evidence that it is effective against any disorder. OK, among the things any non-homeopath ever needs to know are such diverse elements as: it's worthless, unbelievable and has no scientific evidence for it's principles or its efficacy8. Subsequent posts will give more detail on all of the above, in case the stupidity of it all isn't quite obvious to the reader at first glance.

1 Incidentally, Samuel was wise to be sceptical; the proposed mechanism of action was implausible, and other treatments with similar properties did not show similar effects. the question of how quinine does what it does is still not fully resolved, however we do now have significant empirical evidence of it's effectiveness, although other more effective drugs are now available.

2 We will deal with the logic of this reasoning in a later post.

3 It's getting harder not to take the piss. Again these claims, which are made based on what may superficially appear similar to clinical trials, will be addressed later.

4 A remedy prepared from diseased tissue or other matter (blood, faeces, urine, etc.) which homeopaths tell us have an action much like a vaccine but without any of the associated risks.

5 A claim which, by the way, it is illegal to make in the UK. Which I think this lady may fall foul of were someone to report her for directing people to her website not moments after claiming homeopathy can cure cancer. Also note that she claims she has 2000 years of evidence for homeopathy.


7 From the greek for "other feeling" or "other disease", this is Hahnemann's term for 18th/19th century mainstream medicine, which still persists today as a derogatory term for evidence-based medicine 

8This doesn't really work does it? I'm now starting to think I should have gone with the "What has homeopathy ever done for us?" instead of the "main weapons of the homeopathic inquisition are..." Oh well it's too late now ;)