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Placebo effect

Reviewed by expert Scientifically proven

The mind has a substantial impact on the body, and in some situations, it may even aid in healing. The placebo effect is a phenomenon that occurs when the mind tricks you into believing that a bogus therapy has actual therapeutic outcomes. In rare situations, placebos can have such a strong effect that they can imitate the benefits of natural medical treatments.

Table of contents:
  1. What Is the Placebo Effect?
  2. How psychology explains the placebo effect
    1. Classical conditioning
  3. Expectations
  4. Causes
    1. Hormone Response
    2. Conditioning
    3. Expectation
    4. Genetics
    5. Migraine
    6. Cancer-related fatigue
    7. Depression
    8. Conclusion:

The placebo effect, on the other hand, is considerably more than just optimistic thinking. Many people are unaware that they are reacting to a "sugar pill" when this happens. In medical research, placebos are frequently used to aid doctors and scientists in discovering and better understanding new treatments' physiological and psychological effects. To comprehend why the placebo effect is so crucial, it's necessary to understand how and why it operates.

What Is the Placebo Effect?

The placebo effect is a phenomenon in which some people benefit after being given an inert "look-alike" medicine or therapy. This chemical, sometimes known as a placebo, has no recognized medicinal implications. The placebo might be in the shape of a tablet (sugar pill), but it can also be an injection (saline solution) or a liquid that can be consumed. Most of the time, the patient is unaware that the treatment they are getting is a placebo. Instead, they feel they are the ones who are being treated properly. The placebo is made to appear identical to the natural therapy, but it has no impact on the ailment it is supposed to cure.

How psychology explains the placebo effect

The placebo effect is a fascinating link between the mind and the body that is still not fully understood. We'll go into some psychological causes for the placebo effect further down.

Classical conditioning

A sort of learning is classical conditioning. It occurs when you link an object to a specific answer. If you become unwell after eating a particular meal, for example, you may connect that item with sickness and avoid it in the future.

Because classical conditioning may influence behavior, it may contribute to the placebo effect. Consider the following examples:

  • If you use a specific headache medication, you may come to connect it with pain alleviation. Because of this link, you may experience less pain if you take a similar-looking placebo tablet for a headache.
  • You may link going to the doctor's office with getting better or receiving treatment. This link can then have an impact on how you feel about the therapy you're getting.


A person's expectations strongly influence the placebo effect. If you have preconceived notions about anything, they might affect how you see it. As a result, if you anticipate a drug to improve your mood, you may feel better after taking it.

Many different forms of cues can be used to establish improved expectations. Here are a few examples:

  • Verbal: A doctor or nurse may tell you that taking a tablet would help you get well.
  • Actions: You could feel better if you've taken steps to treat your problem, such as taking a tablet or getting an injection.
  • Social: The tone of your doctor's voice, body language, and eye contact can reassure you and make you feel more optimistic about the therapy.


Why do people's lives alter as a result of phony treatments? While researchers know that the placebo effect exists, they do not entirely comprehend how or why it happens. Why do some people sense improvements even when they are merely given a placebo is still being researched. A variety of circumstances might cause this phenomenon.

Hormone Response

One possibility is that ingesting the placebo caused endorphins to be released. Endorphins are natural painkillers that have a structure comparable to morphine and other opiate medications.

Using brain scans, researchers illustrated the placebo effect in action, revealing that regions with a high number of opiate receptors were active in both the placebo and treatment groups. Naloxone is an opioid antagonist that inhibits both natural and synthetic endorphins. The placebo pain alleviation was diminished once participants were given naloxone.


Classic conditioning, or the formation of a connection between two stimuli resulting in a learned response, is another possibility. A placebo can be used in conjunction with a natural therapy in rare circumstances until the desired effect is achieved.

If you're given the same arthritis tablet frequently to ease stiff, aching joints, for example, you may come to link that pill with pain alleviation. Because you've been conditioned to believe that a placebo that looks like your arthritis tablet gives pain relief, you may still feel it does.


The placebo effect has been proven to be influenced by our expectations or what we feel we will experience. A placebo effect is more likely to occur in highly motivated and anticipate the therapy to succeed.

The passion with which a prescribing physician approaches therapy can influence how a patient reacts. A patient may be more likely to perceive advantages from taking medicine if a doctor appears to be highly confident that the therapy will have the desired impact. This shows that the placebo effect may occur even when a patient is receiving legitimate drugs to treat an ailment.

A person's expectations of whether the drug will impact can be influenced by verbal, behavioral, and social clues.

  • Behavioral: When you take a medication or get an injection to help you feel better.
  • Social: A doctor or nurse's reassuring body language, eye contact, and voice
  • Verbal: Talking positively about treatment with a health care practitioner.


People's responses to placebo treatments may also be influenced by their genes. Some persons are prone to respond to placebos more than others. According to one research, people who have a DNA mutation that codes for more significant quantities of the brain chemical dopamine are more susceptible to the placebo effect than those who have the low-dopamine form. People who carry this gene's high-dopamine variant also have excellent pain perception and reward-seeking.


In a 2014 research, 66 persons with episodic migraines were evaluated to see if medication labeling influenced their symptoms. The following is how the research was set up:

  • For six separate migraine attacks, participants were asked to take a medication. They were given either a placebo or a migraine medicine called Maxalt during these occurrences.
  • Throughout the research, the pill labels were different. They might be branded as placebo, Maxalt, or any combination of the two.
  • Participants were instructed to rate pain intensity 30 minutes into a migraine episode, take their prescribed medication and report pain intensity 2.5 hours later.

According to the researchers, the expectations created by the pill labeling (placebo, Maxalt, or neutral) influenced the pain severity reported. The following are the outcomes:

  • Maxalt, as predicted, offered more relief than the placebo. However, placebo tablets were shown to give more alleviation than a control group that received no therapy.
  • Labeling was crucial! The alleviation rating was ranked based on the labeling for both Maxalt and placebo. Pills labeled as Maxalt were at the top of both groups, neutral was in the center, and placebo was at the bottom.
  • This impact was so significant that a placebo labeled Maxalt was assessed to offer nearly the same level of relief as a Maxalt labeled placebo.

In some cancer survivors, fatigue may still be a lasting symptom. In 74 cancer survivors with tiredness, a 2018 research compared the effects of a placebo to standard therapy. The following is how the research was set up:

  • Participants were given either a tablet clearly labeled as a placebo or their regular therapy for three weeks.
  • People who took the placebo medications stopped taking them after three weeks. Those undergoing standard therapy had the option of taking the placebo tablets for three weeks.

Although being labeled as such, the researchers discovered that the placebo affected both groups of participants after the trial was over. The following were the outcomes:

  • When compared to individuals who received standard therapy, the placebo group reported better symptoms after three weeks. They also reported improved symptoms three weeks after stopping the medication.
  • After three weeks, those standard receiving therapies who elected to take the placebo pill for three weeks noticed an improvement in their tiredness symptoms.


The placebo effect was explored in 35 persons with depression in a 2015 research. At the time of the study, none of the participants were using any additional antidepressant medicines. This is how the research was set up:

  • Each participant was given a placebo tablet to take. Some were designated a fast-acting antidepressant (active placebo), while others were established as a placebo (the inactive placebo). The tablets were given to each group for a week.
  • A PET scan was used to monitor brain activity after the week. The active placebo group received a placebo injection during the scan and was told to boost their mood. There was no injection given to the inactive placebo group.
  • For another week, the two groups exchanged pill kinds. At the end of the week, a second PET scan was done.
  • After then, all of the individuals were given antidepressant medication for ten weeks.

Researchers discovered that some people experienced the placebo effect, which influenced their brain activity and antidepressant response. The following were the outcomes:

  • When patients were given the active placebo, they reported more minor symptoms of depression.
  • According to PET scans, taking the active placebo (including the placebo injection) was linked to increased brain activity in regions related to emotion and stress control.
  • At the end of the trial, people who showed higher brain activity in this area frequently had a better reaction to the antidepressants they were given.


A placebo is a drug, pill, or other therapy that appears to be a medical intervention but is not. Placebos are especially significant in clinical trials, as volunteers in the control group are frequently given them.

A placebo should not affect the ailment because it isn't an active medication. Researchers can compare the placebo's findings to those of natural medicine. This aids them in determining the efficacy of the new treatment.

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