What is the Placebo Effect?

The placebo effect is the response from a person from an intervention, for example, a tablet, that contains no active ingredients but elicits a perceived response within the body. A placebo pill typically contains substances such as starch, saline or sugar.

In research, studies often use two groups of patients, one that receives a real medication, with the other receiving the placebo. These sets of patients do not know which group receives what pill. The effects are then measured. The patients receiving real medicine may show side effects or other beneficial or negative responses that could be linked to the medication. Those in the placebo group may also show responses, however, as they have not received the real medication, these responses are known as the ‘placebo effect’.
The placebo effect links the mind and body of patients. If a person believes the tablet they take will help them, then their body may show positive changes. This cannot be linked to a medication, as the pills they receive contains no actual medicine. It is believed that the placebo effect works due to the thoughts and feelings of the patient resulting in physical changes within the body. If a patient believes they are receiving a treatment, then their body makes physiological changes to reinforce that belief.

The placebo effect is most commonly synonymous with research studies. Studies, whereby patients are randomised into either the treatment or the placebo group, are designed to try and find whether there are significant clinical differences between the medication, compared to the placebo. For a medication to be considered beneficial, it must have more positive outcomes than the placebo group.