Editorial – Nocebo effects and negative suggestions in daily clinical practice - forms, impact, and approaches to avoid them

Review written by Sam Spinelli info

Key Points

  1. A large part of our therapeutic outcomes is associated with placebo and nocebo effects. Ignoring them can not only reduce benefit to patients, but may cause harm.
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In healthcare we look to optimize our results and do as little harm as possible. This is generally applied to our interventions, but we often fail to consider placebo and nocebo effects. Traditional belief was that a placebo effect was the resulting change following application of an inert drug or sham intervention; we now know that the placebo effect has a greater impact than we believed and is attributed to factors such as communication, attention, direction, safety, comfort, and meaning (1). We have a growing body of research showing just how impactful these things are with studies showing how sham surgeries can have similar effects to standard surgeries, how telling a patient they’re taking an inert drug can still elicit a physiological response, and much more (1).

The nocebo effect can be considered the reverse of the placebo, where instead of having a desired action, we bring about negative effects and side effects occur. This can result from the same factors mentioned for placebo, and this brings to light the concept of where there is a placebo, there is a nocebo (1).

If you were to decide which medication to take between the three in Figure 1, most would select the middle option as it has the most analgesia with the most moderate side effects.

The placebo effect is attributed to factors such as communication, attention, direction, safety, comfort, and meaning.
Symptoms can be induced, worsened, or negated by our chosen language and method of communication.


What’s interesting is that the middle medication is a placebo. It not only has an effect on pain reduction, but it can also have side effects similar to that of pharmacological interventions. These symptoms were not imagined and are heavily impacted by the words, connotation, and meaning expressed about expected results. The way we express something to a patient can set a negative expectation, which could impact current outcomes, and future outcomes (1).

It’s human nature to use our past experiences to create a future expectation. However this can cycle and become a self-fulfilling prophecy. When patients speak in absolutes or consistent negatives, such as “I always wake up with back pain”, it can build more negative programming. One aspect of our role as therapists is to break this cycle and introduce consideration of when this isn’t the case. This can be done with techniques such as verbal mirroring and using ‘w-questions’, such as “I understand you often wake up with back pain, are there times you don’t wake up with back pain?”. This can help challenge expectations.

It’s important to avoid generating new negative expectations, as if you begin to expect negative experiences it can increase the likelihood of further negative outcomes. Appropriate communication becomes critical here. Symptoms can be induced, worsened, or negated by our chosen language and method of communication (1,2). Zech et al (2019) conducted a study where the researchers measured shoulder strength and found that when risk information was provided in regard to a pain catheter, shoulder strength decreased (2). However, when the researchers provided the same information but also added information about the benefits of the treatment for the patient, there was no reduction in strength observed. This highlights the necessity of appropriate patient education.

When patients are in situations with stress and pain, they have elevated suggestibility and attention. This can make the environment, body language, and verbiage highly impactful. How we have entryways designed, lobby and waiting rooms arranged, clinics set up, and how we act face to face with the patient can alter our outcomes.

An interesting study from Chooi et al (2013) examining a shift in wording from pain to comfort when giving a numerical rating scale following Caesarean section not only changed the patients’ level of pain (reporting less when rating it on a comfort scale), but they also requested less analgesics and viewed their surgery more as wound healing instead of tissue damage (3).

All of these effects are highly dependent on the relationship between the patient and the practitioner. If you consider the idea of walking down the street and being hit on the back - if you turn around and it’s an old friend, you’re more likely to be happy and have no pain; if you turn around and it’s a stranger, you’re more likely to be in pain and be fearful - same event with different outcomes. We should aim to foster a positive relationship with our patients to optimize treatment outcomes.

If we can begin applying the above to our daily practice, we can improve our education, reduce nocebo, and optimize placebo in favor of positive outcomes for our patients.


Hansen E, Zech N. Nocebo effects and negative suggestions in daily clinical practice - forms, impact and approaches to avoid them. Front. Pharmacol. 2019. doi:10.3389/fphar.2019.00077.

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