Nocebo Effects, the Dark Side of Placebo

We easily appreciate the placebo effect – the simple expectation of a treatment’s success positively affects its efficacy.  To prove a new treatment’s utility, then, we compare it against a placebo – a sham with the same expectation of success – to reveal a true magnitude of benefit (or harm).

However, much less appreciated is the flip side: nocebo effects.  I.e., if  patient expects to have adverse effects from a treatment, they are more likely to do so.  This has implications for clinical trials, of course, but also for discontinuation of therapy in general practice.  For example, consider those lovely pharmaceutical commercials, showing happy couples skydiving, in bathtubs, or otherwise living faux healthy lives – while simultaneously providing the droning voice-over detailing a litany of dire, disabling side effects.  Each mention of adverse outcome increases the likelihood a patient will perceive or experience it, and thereby potentially harm patients through decreased adherence to otherwise beneficial treatment.

Nocebo – Darren Cullen (2012)

These authors review the causes and implications of nocebo effects, and have several recommendations regarding effective strategies to minimize nocebo effects.  My favorite, by far:

“Refer to web-based and other information systems that provide evidence-based information, instead of unproven, anxiety-increasing comments.”

Ah, yes – you mean, basically, the entire Internet: insane, uninformed, anecdotal.  Good luck with that.

“Avoiding Nocebo Effects to Optimize Treatment Outcome”
http://www.ncbi.nlm.nih.gov/pubmed/25003609