Nocebo Effect

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Nocebo Effect Definition

The nocebo effect, the opposite of the placebo effect, is a negative reaction caused by a non-medicated control substance, such as a sugar pill. In the placebo effect, a patient experiences the benefits of a medicine under trial, without receiving the medicine. This is thought to be caused by the underlying belief of the patient that the treatment they are receiving will bring beneficial effects. The nocebo effect is similar, in that the patient’s expected outcomes can manifest real symptoms. Often, the nocebo effect is observed when patients are told potential side-effects of a drug, but are only given the placebo, or non-medicated treatment. If patients manifest the side-effects they were told about and never took the drug, this is a clear example of the nocebo effect.

The placebo and nocebo effect have similar causes. In both cases, the body is reacting to what the mind expects. While doctors and scientists first denied the mind’s ability to manifest symptoms or cures, the effect is well documented, as is its counterpart. Apparently, a patient’s expectations can be just as damaging as real chemicals which are introduced to the body. This has been documented in a number of clinical trials, and the nocebo effect itself can introduce a wide array of symptoms, or even increase the symptoms already present.

Meaning of the Nocebo Effect

The phrase nocebo effect was derived after the phrase placebo effect, which means in Latin, “I shall please”. Nocebo effect, as the opposite, means “I shall harm”. The differences in these phrases describes not what type of medicine or fake medicine administered, but is rather a reflection of the patient’s attitude toward the medicine. Those who experience the nocebo effect are consciously or subconsciously under the impression that the medicine they are taking will do them harm. This can be a sugar pill or actual medicine. The nocebo effect, while still present and active in those that took a real medicine, cannot be distinguished from real side effects. In the patients who took a placebo, or fake pill, any side effects seen were caused only by the patient’s mind, as they didn’t take any medicine.

Medical Implication of the Nocebo Effect

Researchers trying to study the effects of their medicine must take extra precautions to detect and exclude symptoms caused by the nocebo effect, as well as those caused by the placebo effect. The standard operation for controlling for these effects is to introduce a placebo into the study. The placebo treatment, which appears to be the same as the medicine but is inert, can show the nocebo effect. It must be remembered that this effect could also be affecting those who took the medicine. Therefore, any symptoms in that group could be any combination of the nocebo effect and the medicine. Scientists can use the baseline effect observed in the placebo patients to understand how much the nocebo effect is adding to the observed symptoms.

While this is a serious concern for medical practitioners, there is another reason the nocebo effect should be studied. Clinical trials have been conducted in which patients experiences symptoms not actually caused by a medicine, simply because they were told it would happen. In effect, the nocebo effect is the mind alone causing visible and quantifiable bodily reactions. The lesson to be learned is that a patient can do damage to themselves if they are not in the right mindset. On the other hand, the placebo effect has shown that patients can improve significantly only on the idea that the medicine or treatment will heal them. Therefore, doctors and researchers should see the nocebo effect as a way to judge the mindset of their patients. Further research is needed into how the mind can play a crucial role in affecting the healing process.

Another concern arising from the nocebo effect is the effect that advertising and negative announcements cause on medicated patients. Some studies have even suggested that telling someone on a certain medication that it can have negative effects will help manifest those symptoms. A serious concern includes inducing nocebo effects in a patient who normally had no side-effects.

The nocebo effect can manifest in a number of different ways. Everything from rashes to pain to changes in body chemistry have been observed as part of the nocebo effect. Other conditions which don’t have a clear cause, could also be related to the nocebo effect. For instance, electromagnetic hypersensitivity is a sensitivity to electronic devices. While there is no understood reason why someone would be affected by normal electronic devices, people suffering from the condition feel pain, headaches, and can even develop visible symptoms from electromagnetic fields. One theory on this condition is that these people are suffering from the nocebo effect, or simply the idea that these devices are harmful to them. More research needs to be done on if the nocebo effect can be reversed through therapy.

A final and significant concern the nocebo effect raises is that of patients giving up early, based solely on their expectations. If a patient expects a treatment to fail, the success rate of that procedure drops tremendously. Real symptoms and perceived symptoms can often not be distinguished from one another. Studies have shown that the effect also increases as the price and stress of a situation increases. Expensive treatments are must subject to both the placebo and nocebo effects because the patient has attached such a high material value to it. While the mind used to be considered separate from the actions and performance of the body, it is becoming increasingly clear that both the mind and body must be in a good place for treatments and medicine to work properly.

Quiz

1. A patient is in a trial of a new drug. The patient shows up at the testing center and is administered a pill. An hour later, the patient starts showing negative side-effects. Is this the nocebo effect?
A. Yes
B. No
C. Maybe

Answer to Question #1
C is correct. It depends on whether the patient was given the actual medicine, or the control placebo treatment. If they were given a placebo, this is probably the nocebo effect. If the patient took the actual treatment or medicine, then this could be either the nocebo effect or actual effects of the medication.

2. Why is it important to test for the nocebo effect?
A. To determine which effects are created by the drug
B. To exclude patients who don’t have the right mentality
C. It is not important

Answer to Question #2
A is correct. The nocebo effect will show which effects were created by the patients themselves. Without measuring this, a researcher can’t understand what caused the effects of the medicine. While the side effects could have been caused by the medicine, they could’ve also been caused simply by the patient’s mind.

3. In the practice of Yoga, people try to improve their wellbeing by exercising their minds and bodies together. What can the placebo and nocebo effect tell us about the effectiveness of this practice?
A. Yoga is a joke
B. While it might work, it is just a trick of your mind
C. It really can work

Answer to Question #3
B is correct. Perception, as they say, is everything. Yoga and meditation work, if properly applied, because they focus the mind on positive outcomes. It is known that while the nocebo effect produces negative outcomes, the placebo effect produces positive ones. While it might be a trick of your mind, if the outcomes are positive, then it works. While it may seem like magic or nonsense, remember that your body is totally connected via your nerve cells, which is entirely affected by your brain. If a nerve can send a signal to the brain, why can’t your brain return a signal?

References

  • Colloca, L. (2017, Oct). Nocebo effects can make you feel pain. Science, 358(6359), 44. doi:10.1126/science.aap8488
  • Rothman, K. J., Greenland, S., & Lash, L. T. (2008). Modern Epidemiology. Philadelphia: Lippincott Williams & Wilkins.
  • Widmaier, E. P., Raff, H., & Strang, K. T. (2008). Vander’s Human Physiology: The Mechanisms of Body Function (11th ed.). Boston: McGraw-Hill Higher Education.

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Biologydictionary.net Editors. "Nocebo Effect." Biology Dictionary, Biologydictionary.net, 22 Apr. 2018, https://biologydictionary.net/nocebo-effect/.
Biologydictionary.net Editors. (2018, April 22). Nocebo Effect. Retrieved from https://biologydictionary.net/nocebo-effect/
Biologydictionary.net Editors. "Nocebo Effect." Biology Dictionary. Biologydictionary.net, April 22, 2018. https://biologydictionary.net/nocebo-effect/.

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