Placebo effect (A complete review)

Placebo effect

A placebo is anything that appears to be a “real” medical treatment, but actually isn’t. 

What is a placebo?

A placebo is medication used in any form, perhaps a pill, an injection or other form but which is actually a ‘fake’ treatment. What all placebos have in common is that they do not contain a single active substance meant to affect health.

Placebo effect (A complete review)

How are placebos used?

Medical researchers use placebos during health studies to help them understand what effect a new drug or some other treatment might have on a particular condition.

The general approach is that a set of suitable people are selected for a study, for example a mix of men and women, of mixed ages who get migraines. Then, some of them would be given a new drug to reduce the symptoms of migraine, and others would get a placebo with no medical properties whatsoever. None of the people in the study would know if they had received the real treatment or the placebo.

Researchers then compare the effects of the drug and the placebo on the people in the study. That way, they can determine the effectiveness of the new drug and check for side effects, knowing the subjects on the placebo have received no medication at all.

What is the placebo effect?

Sometimes a person can have a response to a placebo even though it contains no medical content at all. The response can be positive or negative. For example, the person’s symptoms may improve during the course of the study. Or the person may have what appears to be side effects from the treatment, even though they are not receiving it. These responses are known as the ‘placebo effect.’

There are some conditions in which a placebo can produce results even when people know they are taking a placebo. Studies show that placebos can have an effect on conditions such as:

·      depression

·      pain

·      sleep disorders

·      irritable bowel syndrome

·      menopause.

In one study involving asthma, people using a placebo inhaler did no better on breathing tests than sitting and doing nothing. But when researchers asked for people’s perception of how they felt, the placebo inhaler was reported as being as effective as medicine in providing relief.

Placebo effect (A complete review)

 If a person expects a pill to do something, then it’s possible that the body’s own chemistry can cause effects similar to what a medication might have caused.

How does the placebo effect work?

Research on the placebo effect has focused on the relationship of mind and body. One of the most common theories is that the placebo effect is due to a person’s expectations. If a person expects a pill to do something, then it’s possible that the body’s own chemistry can cause effects similar to what a medication might have caused. It’s a bit like manifesting what you want by visualizing with all your being that you already have it.

For instance, in one study, people were given a placebo and told it was a stimulant. After taking the pill, their pulse rate sped up, their blood pressure increased, and their reaction speeds improved. When people were given the same pill and told it was to help them get to sleep, they became lethargic and tired.

Experts also say that there is a relationship between how strongly a person expects to have results and whether or not results occur. The stronger the feeling, the more likely it is that a person will experience positive effects. 

The same appears to be true for negative effects. If people are told they will and expect to have side effects such as headaches, tingling sensations or drowsiness, there is a greater chance of those reactions happening.

The fact that the placebo effect is tied to expectations doesn’t make it imaginary or fake. Some studies show that there are actual physical changes that occur with the placebo effect. For example, some studies have documented an increase in the body’s production of endorphins, one of the body’s natural pain relievers.

The term ‘placebo effect’ is really short-hand for how just our beliefs about the effectiveness of an inert treatment can generate demonstrable health benefits and mindset changes – an apparently incontrovertible demonstration of the near-magical power of mind over matter.

It’s not actually magic, of course. Our beliefs are the subjective response to physical processes in the brain. It is this kaleidoscope of neurochemical and electrical events, and their resultant effect, that underlies the placebo phenomenon. In some cases, the placebo effect can also be interpreted as a form of conditioned response, in which a learned physiological reaction occurs in the absence of the original trigger.

Placebo effect (A complete review)
To research psychologists, the placebo effect isn’t always a phenomenon of wonder, but a methodological nuisance.

What problems does the placebo effect cause in medical research?

One problem with the placebo effect is that it can be difficult to distinguish from the actual effects of a real drug during a study if people experience the actual effects of the drug. Finding ways to distinguish between the placebo effect and the effect of treatment may help improve the treatment and lower the cost of drug testing. And more study may also lead to ways to use the power of the placebo effect in treating disease.

To research psychologists, the placebo effect isn’t always a phenomenon of wonder, but a methodological nuisance. Researchers must go to extreme lengths to rule out the influence of participant expectations, so as to establish which observed effects are truly attributable to an intervention.

What if the patient knows something is a placebo?

For the placebo effect to occur, it is usually considered that a form of deception is required i.e. tricking the patient into thinking that an inert treatment is actually a powerful drug. This need for trickery has long meant that using placebo effects in mainstream medicine is seen as unethical. However, around 2010, researchers reported that people with irritable bowel syndrome showed greater improvement after being given an ‘open placebo’ that they were told was completely inert, as compared to receiving no treatment at all.

It can be assumed that some residual belief and expectation of an effect survives being told that the treatment is physically impotent. Either this, or there is a condition response to the placebo that does not require positive beliefs. More recent research has shown benefits of open placebos for many other conditions including back pain and hay fever. Open placebos “bypass at least some of the conventional ethical barriers” to the clinical use of placebos, according to some experts. Others, however, have highlighted the lack of suitably robust research in this area, and it’s worth noting there have been some null findings – for instance, open placebos failed to speed up wound healing.

What is a placebo physically?

A placebo can be a substance with no identifiable medical effects, like sterile water, an isotonic solution or a sugar pill. A placebo may be a faux treatment that in some cases will create a very real response. 

In most cases, study subjects who don’t know that the treatment they are receiving is truly a placebo instead believe that they are receiving, for example, a $64,000 treatment. The placebo is intended to appear just like the real treatment, whether it’s in tablet, injection or liquid form.

It is important to note that a placebo and the placebo effect are two different things. The term ‘placebo’ refers to the inactive substance itself, whereas the term ‘placebo effect’ means any effects of taking a medication that cannot be attributed to the treatment itself.

Does the physical attribute of the placebo make a difference?

There is evidence that different forms of deceptive placebo vary in their effectiveness. The more powerful we imagine the effect will be, the greater the benefit. This means that four placebo pills have a larger effect than two; and placebo injections (filled with nothing other than saline solution) are more powerful than pills. In fact, in the context of osteoarthritis, a placebo injection was found to be more effective than a real drug. Also, depending on the condition being treated, pills of certain colors and descriptions are more effective than others, such as blue placebo pills making better sedatives than pink ones, and branded placebo pills being more effective than those without any labelling

Placebo effect (A complete review)

Frequently asked questions (FAQs) about the placebo effect:

Are some people more likely to respond to the placebo effect than others?

Certain personality traits are associated with it being more likely that a person will experience the placebo effect. This is logical since the placebo effect depends on our beliefs and expectations, which some of us may subscribe to more readily and enthusiastically than others.

2.    Are some doctors better than others at creating the placebo effect?

Some doctors will be better placed to reinforce the hope and expectation of a placebo than others. A study that involved a placebo injection for the treatment of an allergic reaction found that symptom improvement was greater when the injection was given by a doctor conveying warmth and confidence. 

3.    Can a placebo help with sleep?

There is almost no end to the ways that the placebo phenomenon can manifest. In one instance researchers tricked participants into thinking they’d had more sleep than they actually had, and then observed how this affected their performance the next day.

The researchers achieved this deception by wiring their participants up to various physiological measures and then giving some of them false feedback on how much REM sleep they’d had. After hearing that they’d had an impressive amount of sleep, participants performed better on tests of language and arithmetic.

What is the nocebo effect?

If the placebo effect occurs simply because you believe a given treatment will be beneficial, it follows that if you have negative expectations, this could result in a worsening of your symptoms. That’s exactly what researchers have found and they’ve called this the “nocebo effect”. Intriguingly, nocebo effects can even occur in the presence of real pain-relieving medications, not just inert treatments.

If you want to explore the placebo effect further check out this reading material:

You Are the Placebo: Making Your Mind Matter

The truth is that it happens more often than you might expect. In You Are the Placebo, Dr. Joe Dispenza shares numerous documented cases of those who reversed cancer, heart disease, depression, crippling arthritis, and even the tremors of Parkinson’s disease by believing in a placebo. Similarly, Dr. Joe tells of how others have gotten sick and even died the victims of a hex or voodoo curse—or after being misdiagnosed with a fatal illness. Belief can be so strong that pharmaceutical companies use double- and triple-blind randomized studies to try to exclude the power of the mind over the body when evaluating new drugs.

Placebo Effects

Since publication of the first edition of this book in 2008, there has been an explosion of placebo research, and this new edition brings the topic fully up to date. Throughout, the book emphasizes that there are many placebo effects and critically reviews them in different medical conditions, such as neurological and psychiatric disorders, cardiovascular and respiratory diseases, immune and hormonal responses, as well as oncology, surgery, sports medicine and acupuncture. The psychosocial context around the patient is crucial to the placebo effect, for example the doctor’s words and attitudes, and throughout this is considered.

The Placebo Effect: An Interdisciplinary Exploration

A mere symbol of medicine; the sugar pill, saline injection, doctor in a white lab coat, the placebo nonetheless sometimes produces “real” results. Medical science has largely managed its discomfort with this phenomenon by discounting the placebo effect, subtracting it as an impurity in its data through double-blind tests of new treatments and drugs. This book is committed to a different perspective, namely, that the placebo effect is a “real” entity in its own right, one that has much to teach us about how symbols, settings, and human relationships literally get under our skin. 

Anne Harrington’s introduction and a historical overview by Elaine Shapiro and the late Arthur Shapiro, which open the book, review the place of placebos in the history of medicine, investigate the current surge in interest in them, and probe the methodological difficulties of saying scientifically just what placebos can and cannot do. 

What Is the Placebo Effect? – WebMD – February 2020

Placebos Without Deception: Outcomes, Mechanisms, and Ethics – www.sciencedirect.com – May 2018

The placebo effect, digested – British Psychological Society – March 2019

Placebo effect (A complete review)

Juanita Agboola

Juanita Agboola is the editor in chief of HFNE and an expert in mental health online. She has been writing about online behaviour, mental health and psychology issues since 2012. All Guides are reviewed by our editorial team which constitutes various clinical psychologists, PhD and PsyD colleagues.