Study: Open-Label Placebos Relieve Fatigue in Cancer Patients


It is common for cancer patients to experience fatigue during and after cancer treatment.

Fatigue usually lessens as patients recover, but some patients experience long-term fatigue that gets in the way of the things they want to do.

Mesothelioma survivors are among the many cancer patients who cope with fatigue once treatment ends.

New research conducted by scientists at the University of Alabama at Birmingham and Harvard Medical School shows cancer-related fatigue can be relieved by a placebo pill. This relief even occurs when patients are aware they are taking a placebo, known as open-label placebo.

A placebo is anything that appears to be a real medical treatment, but isn’t. Patients are usually told harmless, inactive pills are active medicine that will treat a given condition.

Open-label placebos seem to undermine the concept of placebos entirely. But this new study showed placebos have an effect even when patients are told the medicine being prescribed isn’t real.

The study, published in Nature Scientific Reports, showed a 29 percent improvement in fatigue severity and a 39 percent improvement in the degree to which fatigue interrupted quality of life.

These results suggest survivors of mesothelioma might experience improvements in fatigue with the help of a placebo pill.

Deception Unnecessary for Placebo to Work

The study aimed to compare the effects of open-label placebo to treatment as usual (TAU) among cancer survivors reporting moderate to severe fatigue.

Participants were randomized to receive either placebo or treatment as usual. Participants were made aware of the placebo effect up front.

Interestingly, researchers found patients’ opinions of the placebo effect did not impact the study’s outcome.

“Some people who thought the placebo wouldn’t do anything had a good response; others who believed it would help didn’t have a response,” said Dr. Teri Hoenemeyer, lead author and director of Education and Supportive Services at UAB Comprehensive Cancer Center.

After three weeks, the participants switched places. The placebo group stopped taking the pills and the TAU group was knowingly offered placebo pills.

After another three weeks, those taking placebo pills reported a significant reduction in fatigue. The group taken off the placebo pills maintained their reduction in fatigue.

This was the first study to demonstrate the lasting effects of an open-label placebo.

The Power of Placebos

Researchers have sought to understand the placebo effect for centuries. The first documented use of a placebo for clinical purposes was in the late-1700s.

Research suggests a significant percentage of any drug’s effectiveness may be caused by the placebo effect. How large that percentage is varies by condition, cultural norms, strength of a patient’s belief and many other factors.

How placebos work is not exactly understood, but researchers suspect a complex neurobiological response is at play.

The placebo effect goes beyond the power of positive thinking. Current theories suggest part of it has something to do with social conditioning regarding how people perceive therapeutic encounters.

For example, people are conditioned to believe a therapeutic encounter with a doctor will lead to healing. There’s an accepted belief that a doctor wouldn’t prescribe something that doesn’t work.

These concepts contribute to certain emotional reactions, moods and behaviors that lead to the placebo effect.

When a person gets sick, they go to the doctor for treatment and then expect the treatment to work. The person monitors their response to the treatment, watching for signs of bad or good reactions, and making adjustments to how they care for themselves accordingly.

“The placebo effect is a way for your brain to tell the body what it needs to feel better,” said Ted Kaptchuk, director of Harvard Medical School’s Program in Placebo Studies and Therapeutic Encounter. “People associate the ritual of taking medicine as a positive healing effect. Even if they know it’s not medicine, the action itself can stimulate the brain into thinking the body is being healed.”

Placebos in Cancer Research

Many of today’s clinical trials involving cancer patients don’t use placebos. That’s because it is considered unethical to leave a patient untreated when effective treatments are available. Instead of placebos, researchers use standard-of-care treatment.

However, some trials combine standard-of-care treatment with a placebo. For example, a clinical trial might offer standard-of-care chemotherapy to all participants, with some participants receiving an experimental drug and others receiving a placebo.

Some mesothelioma patients are reluctant to join a clinical trial because of fear of receiving a placebo. This fear is important to discuss with your oncologist, who can clarify which trials might involve a placebo.

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Joining the team in February 2008 as a writer and editor, Michelle Whitmer has translated medical jargon into patient-friendly information at for more than eight years. Michelle is a registered yoga teacher, a member of the Academy of Integrative Health & Medicine, and was quoted by The New York Times on the risks of asbestos exposure.

6 Cited Article Sources

The sources on all content featured in The Mesothelioma Center at include medical and scientific studies, peer-reviewed studies and other research documents from reputable organizations.

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  2. Rohan, A. (2018, February 9). Placebo pills prescribed honestly help cancer survivors manage symptoms.
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