• Patricia Faust

The Placebo Effect - Real or Imagined?

We are hearing about clinical drug trials to evaluate a possible vaccine for COVID-19. A treatment group is compared to a control group. The treatment group receives the drug compound being investigated. The control group receives a placebo. None of the people in the study will know if they got the real treatment or a placebo.

Why do they run a study this way? Researchers compare the effects of the drug and the placebo on the people in the study. That way, they can determine the effectiveness of the drug and monitor side-effects.

The Placebo Effect

Placebo controlled studies are the cornerstone of medical research. No study testing a new drug or procedure is approved without evidence that it performs better than the control group. Even when the control group showed improvement, researchers did not know the mechanism of how it worked. So, placebo was relegated as evidence of coincidence. They became an annoyance when the control group made improvements. If the study group and the control group came out with comparable results the study was stopped. At that point the decision was to study placebos.

A placebo can be anything that seems to be a real medical treatment but isn’t. (e.g. pill, injection, cream, surgery, or other treatment). What all placebos have in common is they contain no active ingredients that can affect your health, but after taking them you feel better. The active ingredients of placebo are:

· The therapeutic ritual

· Social and emotional context

· The clinician/patient relationship

Placebo studies have found that when clinicians deliver treatment in a warm, supportive manner, they can influence treatment outcomes. (Dr. Sarah McKay, Neuroscience Institute)

There are certain conditions that respond positively to placebos:

· Depression

· Pain

· Sleep disorders

· Irritable bowel syndrome

· Menopause

The Power of the Placebo Effect

Professor Ted Kaptchuk of Harvard-affiliated Beth Israel Deaconess Hospital Medical Center, stated that “Placebos may make you feel better, but they will not cure you. They have shown to be most effective for conditions like pain management, stress-related insomnia, and cancer treatment side effects like fatigue and nausea.” The action of placebos is still not understood but it involves a complex neurobiological reaction that includes everything from increases in feel-good neurotransmitters, like endorphins and dopamine, to greater activity in certain areas of the brain linked to moods, emotional reactions, and self-awareness. “The placebo effect is a way for your brain to tell the body what it needs to feel better,” says Kaptchuk.

Placebo Effects Arise from Expectations

That is a prevailing idea that placebo effect is the result of positive thinking. Contrary to this belief, patients do not just imagine placebo responses. Numerous brain-imaging studies have confirmed that placebos cause measurable changes in neurobiological signaling pathways. When you expect a pill to have therapeutic value, this expectation activates reward pathways in the brain, in turn stimulating the release of substances called endorphins, which are chemically similar to opiates like morphine. Like morphine, these endorphins bind to opioid receptors and cause pain relief. Therefore, in response to positive expectations of treatment, your brain becomes flooded with its own supply of natural pain killers.

Placebos can also increase the release and uptake of dopamine, a neurotransmitter involved in reward-motivated behavior and decreased pain sensitivity. In anticipation of benefit when a placebo is given, dopamine receptors are activated in the regions of the brain associated with reward.

The most startling placebo-related discovery is placebo is not just one mechanism. Instead, there are as many placebos as there are illnesses and treatments. They act in different ways, at different times, and even impact people differently depending on a number of factors, including genetics. Finally, as proof that placebo effect is a genuine biological phenomenon, genetics can influence the strength of the effect.

As a psychosocial contextual cue that elicits a biological response, placebos can be words, rituals, or any other input that creates expectation.

The very act of expectation changes your brain, but it doesn’t work alone. This is a complex action. Memory and motivation also impact placebo. Moderation of anxiety, activation of the brain’s reward centers and learned responses all play a role.

Placebo Effect Is Real

The placebo effect is real. Research is evolving into various ways that the Mind-Body connection can heal us. Honoring the ability of our mind-body connection to heal us is a profound shift in medicine. We are lucky to have this modality for safe healing.


Harvard Health Publishing, Harvard Medical School. (August 19, 2019). The power of the placebo effect. Harvard Men’s Health Watch.

McKay, S. Placebos & the power to heal. The Neuroscience Academy

Pinch,B. (September 14, 2016). More than just a sugar pill: why the placebo effect is real. Retrieved from

WebMD. What is the placebo effect? Retrieved from

Wildermuth, E. (October 30, 2017). Placebo in the brain. Retrieved from