placebo

A substance or treatment with no therapeutic effect, used as a control in testing new drugs; also, any beneficial effect produced by such a treatment due to the patient's belief in it.

• placeboeffect (n) 安慰剂效应

• placebo effect
• placebo-controlled trial
• placebo group
• placebo response
• give a placebo
• placebo surgery

1. 1.In clinical trials, about 30% of patients receiving a placebo report improvement — demonstrating how powerfully belief can influence physical healing. (inert treatment)
2. 2.The placebo effect even works when patients know they're taking a placebo — "open-label" placebos still produce measurable benefits for conditions like chronic pain and IBS. (psychological healing mechanism)

• sugar pill (informal for an inert medication)
• sham treatment (a fake medical procedure)

from Latin "placebo" (I shall please) — from the Catholic vespers prayer for the dead, "Placebo Domino" (I will please the Lord) — later applied to flattering or ineffectual treatments