What is the Placebo
Effect?
It’s a phenomenon whereby an inert substance believed by a
patient to be a drug has effects similar to the actual drug, resulting in the
patient’s medical improvement. It’s been called the “ghost in the house of
biological medicine” – and, unsurprisingly pharmaceutical companies go to
enormous lengths to exorcise it.
All drugs must show that they are better than a placebo
before they can get a license. This means there’s a campaign to discredit all
forms of non-drug medicine by dismissing any reported benefits as simply due to
the placebo effect.
A Placebo in Action
In one study, subjects were either told they were getting a
painkiller or untruthfully that they weren’t, before having something hot
pressed against their leg. This prior information had a big effect.
Those in the group who thought they weren’t getting any pain
relief reported as much pain as if they really hadn’t had any painkiller – a
simple instruction could wipe out the benefits of a strong drug. The other
group reported much more benefit than was normal in subjects who didn’t know if
they were getting a drug or a placebo, as happens in regular trials.
How should Placebos
be used?
The big objection to using placebos has always been that it
involve lying to patients. No one’s going to respond if they know it’s fake,
right?
But Ted Kaptchuk of Harvard Medical School discovered that
even when he told IBS patients that their pills were placebos – in a bottle
marked “Placebo” – they still reported nearly twice as much benefit as those
who got nothing.
This shows that pretending humans are just biochemical
machines responding to chemical inputs is to miss a huge part of what goes on,
not just in healing but also in our lives.
Extracts:
·
The Lancet recently devoted a major article to
the placebo effect…because scientists have been making some remarkable
discoveries. In fact the line between a drug and a placebo is looking increasingly
blurred.
·
Professor Fabrizio Benedetti of Turin University
is one of the pioneers of this new view of placebo. He’s been shaking up
conventional thinking by showing that, without the placebo effect, some widely
used drugs don’t work at all. He discovered this by doing something quite
simple: he didn’t tell patients they were getting the drug.
·
Summary of Benedetti’s study: two groups of pre-operative
patients – anxious – catheter for anti-anxiety drug – only one group visited by
attentive doctor – only those who saw the doctor got any benefit from the drug.
When the experiment was done with a powerful painkiller such as morphine, those
not visited by the doctor needed almost double to dose to get the usual effect.
“The conventional idea is that a real drug is better than a placebo, but here
the drug didn’t work without the help of a placebo.”
·
Irving Kirsch’s work also suggests there’s a
serious flaw in the way drugs are normally tested. The aim of clinical trials
is to prevent people knowing if they’re getting the drug, so any effect has to
be due to the chemical effect. But 70% of patients in trials for SSRI were able
to work out from the side effects if they were getting the drug or not. One
worrying implication is that drugs with stronger side effects are likely to
show up as more effective in trials.
·
What this shows is that the notion of any clear
division between proper medicine that has no truck with complementary-type
medicine that depends on it, is nonsense. Brain-scan studies have shown that when
placebo effects are at work, they have just as clear an effect on the brain as
a drug does. So if the placebo effect is a vital part of all forms of
treatment, why not find out more about it and make use of its power?
·
Prof. Ted Kaptchuk of Harvard Medical School has
been investigating. He’s already found that there isn’t just one placebo effect
– there are many, depending on the situation. For instance, there’s your belief
as a patient (“I’m about to get a drug that will help”), and there are your thoughts
about your doctor (“He/she seems really nice”). A recent study found that
diabetes patients treated by a doctor rated high on empathy had better
blood-sugar control and lower cholesterol than patients on the same drugs
treated by doctors who were seen as distant. How much the doctor believes in
the treatment – a phenomenon called placebo-by-proxy – can have a big effect
too.
·
Kaptchuk found that you can boost the placebo
element of a treatment by combining these different sorts of placebo response.
“We treated irritable bowel syndrome (IBS) with either just sham acupuncture (a
toothpick) or sham plus lots of emotional warmth and care from the doctor,” he
says. A third group was left on a waiting list as a control.” We found that
those getting just the sham treatment reported 40 per cent reduction in
symptoms compared with those on the waiting list, but those with the boosted
placebo-plus had a 60 per cent improvement. That’s the level of benefit you get
with the best drug.”
·
The truth is that we’re social creatures who
respond emotionally to the world around us all the time. Rejecting placebo
means ignoring that side of ourselves that we value most. The same emotional
responses that power the placebo come into play when we care for our children,
when we make friends, or when we decide to trust someone.
·
Clinics based on the idea of getting the most
out of our natural placebo response would be a path to a more generous,
patient-centres sort of medicine. Could this be one of the ways out of
Drugged-Up Britain?
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