If you don't know what a placebo is, then you should take a moment now to go and look them up (there's plenty of information on this website). Placebos describe the fascinating phenomenon through which a sugar pill can have all kinds of profound medical effects on the body due simply to the belief that they will. In other words, if you think you've been given a magical cure for insomnia, you may well start to sleep better again at night. Like I say, you should go and read more on it because the effects can be shockingly wide ranging and pronounced. This isn't just a case of people tricking themselves into believing something works, the belief can actually bring on measurable chemical changes in the brain and body which are just as 'real' as those created by medications.
The Problem With Placebos and Medicine
As you might have imagined, this then creates a problem for pharmaceutical companies and researchers trying to look into the effects of new drugs. Give someone a new pill to test, and they will probably find that it 'works' regardless of what's in there simply because they expected it to. So how does a company know when they have something that 'genuinely' works, or something that just acts as a placebo?
For a long time now the answer has been the 'double blind experiment'. What this means is that the test subjects will be split into two groups, with one group receiving a sugar pill, and the other group receiving the real drug.
Crucial to this type of 'experimental design' is the fact that the test subjects don't know which pill they're getting – and neither do the experimenters themselves. This is considered the 'gold standard' in experimental design as there's no way that the experimenters can even accidentally give away anything that would influence those in the experiment. The assumption then is that while both might have a placebo effect, any effects above and beyond that placebo must be a result of the drug working.
But it turns out that even this may not be enough, and thus experimenters are having to find even more creative ways to rule out placebo effect.
The Problem With Double Blind Experiments
The problem is, that the placebo effect is so profound, that even in double blind experiments it seems to be influencing and damaging the results.
Fabrizio Benedetti is a researcher examining this problem and in one study he demonstrated how beliefs regarding the effectiveness of an analgesic called 'CCK-Antagonist' may be incorrect.
In double-blind randomized trials, CCK Antagonist proves to be an effective medication for treating pain. However, when Benedetti tried giving subjects the medication without telling them that they would receive it, he found that the results were nowhere to be seen. If the treatment was genuinely an effective painkiller, then in theory it should work whether or not the patient knew about it – but this proved not to be the case.
It turns out that CCK is not an effective painkiller on its own, but is rather a 'placebo amplifier'. What this means is that the medication combined with the chemical reaction in the brain caused by the placebo effect is what gives it its power. And it seems that this may be true of many well-known and popular medications, including big names like Diazepam and even morphine to some degree (it takes a much larger dose to have an effect when a patient doesn't know they're receiving it).
Other interactions might also take place to confound results. For example, it could be that a drug makes someone feel a little light-headed when taken. In this situation the patient would 'feel' as though 'something' was happening, and would likely interpret that as the drug being effective. This could then trigger a much stronger placebo effect, even if the drug doesn't work in the capacity that it's prescribed. Likewise if a drug made someone feel happier or more optimistic through a neurochemical effect, this could also strengthen the impact of placebos.
Just to compound these problems, drugs that we know don't have any chemical effect have been shown to pass double blind experiments, just as drugs that do have a measurable effect have been seen to fail them. With placebos being so powerful, varied and complex, how can we ever be sure that a drug really works?
Problems and Solutions
There are those who look at these findings and ask why it should matter. As long as a drug has the desired effect, does it matter whether it's from the medication itself or from the patient's belief?
That's one way of looking at it, but unfortunately it's still not that clear cut. While in some cases placebos actually can help people overcome illnesses, they can also make us think we're getting better without actually fixing anything.
Likewise there is a serious moral issue surrounding the sale and recommendation of drugs and pills that don't do anything. Would you be happy with your doctor if they recommended you paid $10 for a pot of sugar pills? This actually happened to me when a doctor recommended I used a homeopathic remedy to treat scars on my face. I trusted the doctor without reading what was on the back of the pot, and surprisingly enough it turns out placebos are not that effective in treating scars.
For research purposes too, it's crucial that we are able to identify when changes are happening in the body in order to develop new treatments and provide useful medical advice.
So what's the solution? How do we identify when something is working mechanically and when it's really just a placebo? Benedetti suggests two methods, though neither is without its own problems…
Hidden Treatment: The 'hidden treatment' approach would involve giving test subjects medications without telling them they were receiving them. This way there would be no way for the placebo effect to become an issue, but it is also riddled with a number of ethical problems. How do you get informed consent from a participant who doesn't know they're going to be tested on?
Benedetti suggests that the answer to this problem would be to tell patients they are going to receive a treatment but not tell them when. Theoretically you could also tell patients they were going to receive a treatment but not tell them what it would do.
Balanced Placebo Approach: Another option is the 'balanced placebo' approach. Here you would have four groups of participants – one receiving the sugar pill and being told it was a sugar pill, one receiving the sugar pill and being told it was the treatment and two more receiving the real medication with the correct and incorrect information.
It's also worth noting however that animal trials would not be affected by placebo – meaning that we can still be relatively certain of the effects of some medications when comparing human and animal trials. So don't be too alarmed – most of the medications you're prescribed will still work and even if placebo plays a part it shouldn't matter.
That said, it's still interesting to learn that the trials we have previously relied on to test medications may not be as bullet proof as was previously thought. The power of placebo is so impressive that it's called into question the effectiveness of countless treatments and medications we take for granted. The search for the truth just got more difficult…