medicines

Placebo

プラセボ（偽薬） (purashebo (nise-gusuri))

A placebo is an inactive substance, device, or procedure used in clinical trials as a comparison to the experimental treatment. Participants may receive either the real treatment or a placebo without knowing which they received — this is called blinding. The placebo effect refers to real physiological improvements some patients experience even when receiving an inactive treatment, due to expectation and belief. Placebos are critical to rigorous clinical research design. Outside of trials, providing placebos without disclosure to patients raises ethical concerns.

Randomized, placebo-controlled trials are the gold standard for evaluating new medical treatments before FDA approval.

In 9 languages

Language	Term
English	Placebo
Japanese (日本語)	プラセボ（偽薬）
Chinese (中文)	安慰剂
Korean (한국어)	위약
Portuguese	Placebo
Spanish	Placebo
Filipino	Placebo
Thai	ยาหลอก
Vietnamese	Giả dược
Romanization	purashebo (nise-gusuri)

Related terms

• Clinical Trial 臨床試験
• Informed Consent インフォームドコンセント
• IRB (Institutional Review Board) 治験審査委員会（IRB）
• Off-Label Drug Use 適応外使用

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