NOCEBO

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The Nocebo effect occurs when a person's negative expectations, fear, or anxiety about a treatment or substance cause them to experience real physical or psychological harm, even if the treatment is inert (such as a sugar pill) or non-pharmacological. The term comes from the Latin word nocēbō, meaning "I shall harm". The term "nocebo effect" was first used in 1961. It was coined by a British physician named Walter Kennedy in a medical paper where he noted that while a "placebo" describes a pleasing response to a dummy treatment, there was a clear, contrary reaction where patients experienced negative symptoms purely out of expectation. He selected the Latin word nocebo ("I shall harm") specifically to serve as the direct evil twin to placebo ("I shall please"). Pretty much explains it.