Placebo and nocebo are two words that are antonyms. Antonyms are words that have opposing meanings. We will examine the definitions of the words placebo and nocebo, where these terms came from and some examples of their use in sentences.
A placebo is a procedure or medicine that works to heal a patient due to a psychological effect, not a physiological effect. A placebo works because a patient believes it will work, not because of any chemical or biological reaction stemming from the procedure or medicine itself. This phenomenon is called the placebo effect. The term placebo was first used in medicine around the turn of the nineteenth century, to indicate a medicine given to a patient in order to appease him, rather than to treat him. Placebo is a Latin word that means I will please.
A nocebo is a procedure or medicine that harms a patient due to a psychological effect, not a physiological effect. A nocebo harms a patient because that patient believes it will harm him, not because of any chemical or biological reaction stemming from the procedure or medicine itself. This phenomenon is called the nocebo effect, and is often observed when a patient is made aware of the possible side effects of a medicine. The word nocebo was coined in the 1960s, patterned on the word placebo, using the Latin word nocere, meaning to harm.
A placebo and the ‘real’ treatment are administered, and if both the placebo and the real treatment produce positive change then the treatment is deemed ineffective, or at least no more effective than a ‘sham’ treatment. (The Adelaide Review)
Known as the evil cousin to the placebo effect, the nocebo effect occurs when negative expectations result in negative consequences, which in some cases are tangible physiological changes. (The McGill Tribune)
Physicians should be aware of the placebo and nocebo effects when describing medications to patients, says Per Aslaksen, a psychologist at the University of Tromsø in Norway who researches the placebo effect and who wasn’t involved in the work. (Science Magazine)