top of page

Placebos: The Magic of Medicine

Updated: Jan 15, 2020

By: Adam Tseng

Would you believe it if diseases could be cured without medicine? Obviously not, you'd think. That would be magic, and magic isn't science. But what if there was really a way to help sick people get better - just by using a simple trick of the mind?

The Placebo Effect: How It Works

The placebo effect is a widely known medical phenomenon that combines medicine and psychology. It occurs when patients receive a placebo: a fake intervention, whether it be a sugar pill or a false procedure. The treatment must closely resemble an actual one in order to deceive the patient into anticipating a positive outcome from the medicine. Expecting to feel better after the treatment leads the patient’s condition to actually improve, even though they received no actual medical care.

The reason behind this seeming miracle lies in the power of the brain. As the control center for the body, the brain regulates many senses and functions. Thus, important processes such as breathing and pain perception can change if the mind wills it to. Only a “kick in the door” - a temporary shift of a patient’s mental status - can cause the whole body to follow suit, reinforcing the brain’s state throughout the whole body. While this effect cannot shrink a tumor or eliminate a pathogen, it can alleviate symptoms or pain associated with them. It is especially potent in fighting depression. Because the mind is the sole cause of that condition, the placebo can reverse disease progression by tricking the brain into improving.

Capsule or confectionery? Depends on what your brain believes.


However, a placebo has one major limitation: consistency. While powerful, the placebo effect may not always produce the desired outcome. Sometimes, it does not work at all. Other times, the conditioning effect may occur instead, where an individual may need to experience a positive effect from the real treatment before the placebo can work. In the worst-case scenario, the placebo might actually yield a negative result where the patient’s mind expects to feel worse, leading their condition to deteriorate. This can occur in some trials of experimental drugs, where participants’ perception of pain can be heightened to such a degree that they are forced to drop out of the study. The substantial risk of these adverse effects puts a serious hamper on the adoption of placebos as real medical treatment.

Use in Health Research

Though placebos have been used as controls for clinical trials in the past, this practice has diminished in recent years. Because the placebo given would resemble the actual experimental treatment, the placebo effect would not influence results. However, the ethics, or morality, of this method are questionable. Is it right to give any patient a placebo? After all, administering a placebo is sometimes equivalent to administering no treatment. Thus, this would delay medical treatment for the control group. To avoid this problem, current clinical trials frequently administer the standard or old treatment to the control group and compare it to the experimental one.

The rules for the use of placebos in clinical trials are laid out by the Declaration of Helsinki, which was created in 1964 by the World Medical Organization. It explicitly states that placebos may be used “where no proven prophylactic, diagnostic or therapeutic method exists.” Thus, if there is nothing comparable to the treatment or procedure being tested, a placebo is ethically justified. In some cases, the placebo may still be preferred even with the existence of current treatments. If there is a specific way that a fake treatment can directly determine the effectiveness of the experimental one, or if the current standard of treatment may not be safe, the placebo is used.


Declaration of Helsinki: Recommendations guiding physicians in biomedical research involving human subjects. (1983). World Medical Association.

Harvard Health Publishing. (n.d.). The power of the placebo effect. Retrieved from

Placebo Effect. (n.d.). Retrieved from

Resnick, B. (2017, July 07). The weird power of the placebo effect, explained. Retrieved from


bottom of page