Questions in behavioural economics - Why is the placebo effect important?

Nipuna Senaratne writes about aspects of the placebo effect and some of its consequences for the treatments we make available through the health service.The placebo effect is the medical phenomenon where an external stimulus can have an effect on the efficacy of treatment even if the medication or procedure is fake. This intervention could take the form of a inert sugar pill and may cause the patient to believe that the treatment is both real and effective. This expectation that the treatment will help his or her condition may lead to a therapeutic improvement decreasing symptoms and improving the patient's condition. The physiological effect stemming from 'fake medicine' shows how the brain and body are intertwined and how expectations play a huge role in determining the effectiveness of treatments.

This effect is made all the more interesting by the variations in improvement that can be seen depending on the type of treatment being issued and the inter-comparisons between different placebos. Research seems to suggest that different placebo treatments can have different effects based on the type of treatment but more importantly on the way the treatment is administered. Different coloured pills tend to have different effects on patients reflecting the brain's association with different colours. Green and blue colours that are associated with peace and nature tend to have a sedentary effect whilst brightly coloured pills encased in reds and oranges can be more alerting. In this way the mind relates the colour of the drug (which has no medical bearing whatsoever) with its physiology.

Pharmaceutical companies take advantage of this phenomenon by colouring their drugs in suitably: the packaging on anti-anxiety and anti-depressant pills tend to be blue and white, whilst anti-biotic and stimulant pills take bright red and yellow colours. Salt-water injections (injections containing saline solution that will neither harm or help the body) seem to contribute to a more significant improvement than simple sugar pills. This implies that the severity of the treatment delivered has an effect on the patient's outcome even though both treatments are benign and should give no therapeutic effect at all.

The brain recognises that an injection feels like a more serious treatment than a couple pills and this superficial, neurological process creates far greater expectations of the more severe treatment. In some way the procedure seems more real and the mind relates this to supposed, greater efficacy. Taking a larger quantity of pills can increase the therapeutic effect as it raises expectations about the potential benefit of the treatment. For example, using four placebo pills instead of two has shown to be significantly more effective in clearing gastric ulcers. Neither taking two or four pills should have any effect but they do and this effect is varied. This is underlined further when considering the effect of false surgery (where the surgeon may make an incision but do not carry out an operation); in comparison these tend to be even more effective than false injections.

Patient's expectations can also be shaped by other properties of interventions including expense. If a group of patients (all given the same sugar pill) were divided into two with one group being told they were about to receive an expensive drug and the other being told what they were about to receive was on a special discount, those with the supposedly more expensive drug would have vastly more pronounced improvements. Their greater expectations of what the drug may do arise from the higher price and inexplicably lead to a quicker recovery. Moreover, patients who have had the most recent pain or the most painful symptoms seem to improve the most, their greater need being transferred into greater efficacy.

These examples of placebo all rely on overlying expectations that the drug will be beneficial, expectations that can be strengthened if the drug is more expensive or delivered in a more 'intense' procedure. The idea that the neurological details in the brain can have a physiological effect is difficult to comprehend and goes against all medical thought. This has significance for the scientific community in a number of ways, the most obvious of which being the rise of homeopathy (so called 'alternative medicine').

Having turned to homeopathy, people who do see improvements in their condition, are less inclined to believe that it was their own expectations that healed themselves as oppose to the treatment they received, partly owing to the brain-washing they receive and partly because it seems perfectly logical. You are ill. You go and get homeopathic remedies. You get better. It seems logical and moreover scientific to assume that the remedies were the cure of your ailment. The concept of our own ideas overwhelming reality in this way is difficult to ponder but it is one of the most powerful tools at a medic's disposal.

The next question surely to ask is how this hugely powerful effect could be used in medicine?

Could the NHS provide placebo treatments, in doing so using the patient's own expectations to improve symptoms? Certainly there would be no harmful effects of providing sugar pills and it would be an interesting exercise to see the extent to which the placebo effect worked in numerous other areas of medicine. However, the use of placebo involves direct lying from a doctor to a patient undermining all credibility and trust that is so crucial in such an intimate relationship.

The way in which placebo could be utilised ethically would be in improving the way in which a treatment is given. A greater investment of time, money and thought could be diverted into creating a greater sense of positivity and a friendlier environment. This change of behaviour may have a significant effect on the speed of recovery after normal treatment, instilling a greater sense of hope and expectation within patients that would make existing treatments even better.