Category Archives: Evidence-based medicine

Got chronic pain? Maybe try a placebo

If you have chronic pain and want to avoid pain meds, or even popping too many ibuprofen, maybe you should try a placebo!

The placebo effect is what we call improvement from a treatment when that treatment doesn’t do anything that should help the condition, usually in the context of clinical research. The placebo effect can actually be pretty powerful, and is one of the reasons why doing controlled experiments is so important. In an age where scientists often fail to replicate research, placebos are seen by some scientists and doctors as a promising treatment for some conditions. Leaving aside a number of technical discussions about what the ‘placebo effect’ really is, placebos are cheap, don’t have negative side effects, and the beneficial effects are well documented for some conditions.

‘But doctors can’t prescribe placebos!’ you say. ‘That would be unethical!’ Well, it turns out that placebos can help people even when they KNOW it’s a placebo. Check this out.

Lower back pain is a huge problem all over the world (seriously, it leads to tons of disability cases everywhere). So, in this study Carvalho and colleagues (2016) took adults with persistent lower back pain who were fine taking pills and didn’t take opioid drugs. They also didn’t include people who had pain from a bunch of different causes, like cancer, broken bones, surgeries, and trauma. Instead they were just trying to look at people with lower back pain without any obvious cause. They split everyone up into two groups of people: what they called ‘treatment-as-usual’ or TAU, and an ‘open-label placebo’ group (OLP). So, they actually TOLD the people getting the placebo that they were getting a placebo. All participants had the placebo effect explained to them in a ‘positive’ way. ‘Positive way’ just means they were told that placebos can help people if they are taken consistently, even if there’s nothing in them. 83 people were included in this study.

So what happened? Well, not only did the placebo (OLP) group see improvement in their pain symptoms, but their degree of disability from their lower back problems was actually substantially reduced! Kind of crazy.

How does this work? The idea is basically that the patient’s belief the placebos might help are actually leading to the improvements. Maybe they are just helping patients not notice the pain, or not care as much about the pain. An alternative hypothesis is that simply by seizing some agency, or in other words, by ‘doing something’ about their pain and feeling in control of their situation, the pain can be reduced.

Is this a real effect? Well, yeah. I mean, pain was a problem for the people in this study, and the placebo reduced their pain. A placebo can’t make a limb regrow, won’t kill parasites, won’t cure cancer or mental health problems, and you should probably run away from people saying otherwise. If you have a condition that could be dangerous, placebo treatment instead of conventional treatment is a BAD idea. But for issues like chronic pain, it could provide cheap and easy relief with no negative side effects for many people.

There are certainly some ethical considerations with doctors prescribing placebos (although it’s apparently commonly done in Europe with patients who are drug seeking or who doctors think are hypochondriacs). Most of these considerations are vastly reduced however when patients are TOLD they are being given a placebo, and simply told the truth that the placebo effect is real, and can be powerful. Pretty cool!



  1. Rutherford BR, Mori S, Sneed JR, Pimontel MA, Roose SP. (2012) Contribution of spontaneous improvement to placebo response in depression: a meta-analytic review. J Psychatric Res 2012; 46: 697-702
  2. Chaparro LE, Furlan AD, Deshpande A, Mailis-Gagnon A, Atlas S, Turk DC. Opioids compared with placebo or other treatments for chronic low back pain: an update of the Cochrane Review. Spine 2014;39:556–63
  3. Open Science Collaboration (2015). Estimating the reproducibility of psychological science. Science, 349
  4. Carvalho C, Caetano JM, Cunha, L, Rebouta, P, Kaptchuk TJ, Kirsch I (2016) Open-label placebo treatment in chronic low back pain: a randomized controlled trial. Pain doi: