The placebo effect

The placebo effect

We’re all aware of the placebo effect, and we all think that we understand it – but what about placebos still working even when you know they’re just sugar pills? Or their evil twins, nocebos, that can induce side effects from the same sugar pills?

Most people feel that they have a handle on the placebo effect- that it’s where you feel better after taking a dummy drug or treatment, and that it works because you, and perhaps even your doctor, believe that you’re getting an active treatment. The truth however is far stranger even than that.

Firstly you don’t have to be fooled into thinking that you’re getting a “proper” treatment. Studies and trials with patients with Irritable Bowel Syndrome (IBS) have shown that a significant proportion of those who knowingly received a placebo actively felt better and showed improvement in their symptoms. The control groups in these trials, who were left untreated, didn’t show any improvement at all, leading to a theory that we may be able to actively invoke the placebo effect as part of peoples’ treatment.

Currently this theory is based on the idea that there are a number of genes that deal with neurotransmitters in general, and dopamine in particular. Variations and mutations in these genes are believed to affect up to a third of the population, leaving them with a heightened response to pain relief. This includes the group of IBS patients with a gene mutation that allowed them to consistently use a lower doses when administering morphine to themselves with a pump.

As well as using genetic screening to identify those with greater susceptibility to the placebo effect we may be able to use different personality traits. Studies have shown that those who are naturally extrovert, gregarious, and engage with new experiences have a significantly higher placebo response, with improved responses to stomach ulcer placebo treatments, and to pain relief.

There is also a mirror image to the placebo, known as the “nocebo”. The nocebo effect can be seen in side effects from inert treatments such as sugar pills or saline solutions. In trials these normally correspond strongly both to the potential side effects presented to those taking part, and their individual faith in the ability of the doctors.

It’s the same effect that sees people who exhaustively study the list of side effects on their prescription medicine more likely to report those very side effects. What isn’t clear of course is whether it’s a personality type that leaves them more physically susceptible to side effects, or more likely to cause them following their suggestion. Linked to this is the known effect of more expensive and brand name medication being reported as more effective than the same unbranded or low cost versions. Unsurprisingly this even extends to placebos, with more expensive placebos being reported as more effective than lower cost placebos.

The placebo effect then is real, and potentially points the way forward to personalised treatments for migraine, IBS, and eczema. What there isn’t compelling evidence for though is its existence in the animal world. Although many believe that homeopathy or reiki will help their horse or dog there’s no systematic evidence for it. The problem is that instead of animals being able to report their pain we have to rely on the assessment of their owners, and a mixture of wishful thinking and confirmation bias lead to them systematically, if subconsciously, overstating the improvements.

If you’ve found this interesting why not read about Morgellons syndrome, a physical illness with roots in the mind, or the treatment of migraine with Botox®, or even sign up for my monthly newsletter here with three stories every month on the quirky side of relationships and psychology.