IAN MUSGRAVE/THE CONVERSATION
HOMEOPATHY’S got a bit of a run in the media in recent months and the stories are by no means positive.
It all started in April when the medical press highlighted the National Health and Research Council’s (NHMRC) impending statement on the practice.
The ABC’s Australian Story then broadcast “Desperate Remedies”, bringing the non-medical base of homeopathy into the spotlight, and last week the commercial stations jumped on the bandwagon with Channel 7’s Today Tonight running a story about it.
The NHMRC is still finalising its statement, which, it says is based on one by the UK House of Commons Science and Technology Committee. It has also said it will likely recommend insurers to not pay for homoepathy because studies have found it to be ineffective.
The genesis of homeopathy
Homeopathy is a system of health care based on the idea that “like cures like” – substances that cause the same symptoms as an illness can cure that illness.
And the idea that extremely small dilutions, so small there’s almost no chance of the original substance being present, are more effective than more concentrated solutions.
If the former sounds a bit like alchemy, that’s because it is. “Like cures like” is a fundamental principle of medical alchemy, endorsed by no less than the father of pharmacology Paracelsus.
Homeopathy reflects this idea because when its founder Samuel Hahnemann first formulated his approach in 1796, alchemy was on the wane but still influential.
Medicine looked nothing like it does today at the time, with extreme treatments like bleeding, purgatives and heroic concentrations of opiates in common usage.
Using fruit juice to combat scurvy would only be widely implemented in five years’ time; vaccination lay six years in the future; and the germ theory of disease and the Law of Mass Action over 50 years in the future.
So it’s not surprising that homeopathy became popular: in an era where conventional treatment was just as likely to kill you as cure you, the gentler ultra-dilute tonics of homeopathy would at the very least not harm you.
Medicine evolved as we came to better understand the body and developed effective medicines.
But homeopathy didn’t. It remained mired in the same 18th-century alchemical thinking.
The homeopathic hospitals of the 19th century either closed or were converted (the former Prince Henry’s Hospital in Melbourne, where I used to work, started life as a homeopathic hospital).
A little drop won’t do it
Homeopathy has a symptom-based approach to medicine – it ignores the actual mechanisms of disease. Take insomnia, for instance, the treatment for it is (among other things) “Coffea 30C”.
Coffea is caffeine, the substance in coffee that keeps you awake and the 30C describes how much the caffeine is diluted.
Now, most people would instinctively feel that giving caffeine to someone with insomnia is not the best idea, but the magic is apparently in the dilution.
The C in 30C means the solution has been diluted to one part in a hundred and 30C means the solution has been diluted one in a hundred 30 times.
If you take a drop of your morning coffee and drip it into the nearest dam, the concentration of caffeine in the dam would be higher than 30C dilution of caffeine.
In fact, a 30C dilution is highly unlikely to contain a single molecule of caffeine.
Our everyday experience is that when you dilute something, it gets weaker. Homeopaths claim that, contrary to our experience and the laws of physics, substances get stronger as they become more diluted.
Or, rather than getting stronger, the mirror image of their effect gets stronger. So, caffeine, a stimulant, somehow becomes an effective sleep aid.
Homeopaths have a number of different, mutually contradictory explanations for this. One of the most popular is that water retains a “memory” of the substances in it.
Now if this were true, water would retain the memory of all the substances that have ever been in it, and the effects would be rather obvious to all.
We can see why the dilution can’t work by considering caffeine again. We know that caffeine make us more alert by stopping the action of a brain hormone.
Diluting caffeine out won’t make the brain hormone work harder, nor will a “memory” of caffeine.
Homeopaths’ explanations are incoherent and require everything we know about how the body works to be wrong.
Any apparent effect of homoeopathy is purely due to the placebo effect, where people feel subjectively better just because we are paying attention to them. But the underlying disease doesn’t get any better, and we should never substitute real medicine for placebos.
But does it actually work?
We can talk about theory all day, but what if there was evidence that homeopathy actually worked? That would trump any discussion of theory. Clinical trials have been done on homeopathy, and the results aren’t good.
Now, not all clinical trials are equal but good-quality clinical trials show homeopathic remedies have no effect, whether for asthma, attention deficit disorder or side-effects of cancer medication (podcast here). For some diseases, such as dementia, there are simply no good clinical trials to evaluate.
The most recent evaluation of the evidence for homeopathy was the UK government’s Evidence Check 2: Homeopathy. After reviewing the best scientific evidence and submissions from stakeholders, the review concluded that homeopathy showed no evidence of efficacy.
What’s the NHMRC got to do with it?
The NHMRC is Australia peak body for evaluating and promoting best health practice, so it’s entirely appropriate for it to rule on the effectiveness of homeopathy.
Its rulings have several implications – doctors will be reluctant to prescribe remedies that have no proven efficacy, for instance, and insurance companies will be reluctant to pay out on them.
Australian adults have the right to choose treatments for their aliments (or choose not to be treated). But they need access to the best-available evidence so their choices can well-informed.
Ian Musgrave is senior lecturer in pharmacology at University of Adelaide. This article first appeared on theconversation.edu.au.