Nocebo Effect Explained: Here's How Placebo Effect's Negative Counterpart Works

While several people may already be familiar with the placebo effect, the phenomenon actually has a negative counterpart known as nocebo effect.

A Case of the Nocebo Effect

A 2007 case study highlighted the strong phenomenon, detailing a 26-year-old man's experience of being part of a clinical drug trial looking into an antidepressant medications effectiveness. Before the start of the trial, the man was depressed for two months after his romantic relationship ended.

By the end of the trial's first month, A experienced significant mood improvements. He was at the start of the treatment's second month when he and his girlfriend had an argument. This made him decide to take the remaining 29 capsules.

Before collapsing, he went to the hospital to seek help. Upon assessment, it appeared that he was heavily sweating and pale. His pulse was also apparently elevated while his blood pressure was abnormally low. Though he received six liters of intravenous fluids for more than four hours, he stayed sluggish. His heart rate and blood pressure also stayed abnormal. A doctor involved in the drug trial then went to the hospital and said that the capsules taken by the Man were but a placebo. Within 15 minutes after the news was released, the man became alert, while his pulse and blood pressure went back to the normal range.

ALSO READ : Why Do Placebos Work?

Nocebo Effect

The nocebo effect typically happens when the negative expectations a person holds towards treatment could result in negative side effects. The nocebo effect is essentially the polar opposite of the placebo effect.

Any active ingredients of a procedure do not cause the nocebo effect. Rather, the phenomenon results from psychological factors, including empathy, past experiences, expectation, among others.

Dr. Kate Faasse, a senior health psychology lecturer from the University of New South Wales, has been studying the phenomenon for over a decade. The subjects of the doctor's study include physical symptoms in unsuspecting participants by letting them know of possible side effects. As part of her research, Dr. Faasse makes use of props and stories to make sure that the participants are none-the-wiser regarding her studies' purposes.

It appears that nocebo effects are quite common. A 2011 meta-analysis discovered that roughly 67.2 of patients treated with placebos during clinical trials that involved fibromyalgia medications reportedly experienced at least one side effect. A different meta-analysis also found that 70.6% of patients treated with placebos involving a Crohn's disease treatment reportedly experienced adverse side effects.

Dr. Faasse suspects that, in the right conditions, everyone has the capacity to experience this phenomenon.

Nocebo Effects and Healthcare

There are factors that can boost the likelihood of going through nocebo effects. These factors include an increased expectation that side effects would happen, suggesting that side effects could be experienced due to a medical procedure or medication, individual perceptions that the dose of a medication is higher than usual, and conditioning.

Social modeling is also a crucial predictive factor for the effect. This involves witnessing another person report experiencing side effects.

This phenomenon is crucial in patient care as it could influence the outcomes of treatment. Though several people do not know that such an effect exists, this does not imply that they are protected from its reach. Dr. Faasse says that several people do not know that side effects have psychological influences.

Dr. Faasse also stresses that experiencing nocebo effects do not mean that the symptoms one experiences are "all in the head." The doctor notes that these things truly happen, as the brain is good at fostering symptomatic experiences and making the body feel unwell.

There are potentially negative health outcomes that are carried by nocebo effects. For one, experiencing nocebo effects could lead to discontinuation of important treatment. Moreover, for individuals who carry on with treatments even though there are nocebo effects, significant discomfort could result from the side effects.

Nocebo Effect Reduction

Given how physicians have the legal obligation to let patients know of the treatment's side effects, how exactly can nocebo effects be reduced?

Dr. Faasse says that it is necessary to inform people of potential side effects. However, this can be done in a different manner. The doctor notes that focusing on a positive framing of the side effect information could significantly lower the nocebo effect.

Along with colleagues, Dr. Faase discovered that there are only a few studies that look into the impacts of positive framing on nocebo effects. Out of six, five appeared to show significant reduction in at least one side effect aspect when positive framing was incorporated.

The effect can also be reduced by offering a medical treatment choice. When a limited choice is offered to people, the effect can be reduced or even knocked out.