Placebo

How it is used

Trials are often placebo-controlled: one group gets the drug and the other a placebo. The placebo effect is a real improvement that comes from expecting to get better; the nocebo effect is the opposite, when expecting side effects brings them on. The plural is placebos.

Example sentences

1. Patients in the control group received a placebo that looked exactly like the real tablet.

2. Some of the improvement was probably a placebo effect.

Common collocations

• placebo effect
• placebo-controlled trial
• receive a placebo
• compared with placebo

Related terms

• clinical trialA research study in people that tests whether a new medicine or treatment is safe and works, usually by comparing it with a placebo or an existing treatment.
• double-blindDescribes a trial in which neither the participants nor the researchers know who is receiving the real treatment and who is receiving a placebo or comparator.
• randomized controlled trialA study in which participants are put into groups by chance, one receiving the treatment being tested and another a placebo or standard treatment, so results can be fairly compared.
• efficacyThe ability of a drug to produce the wanted effect; in pharmacology, the maximum effect a drug can produce, however high the dose.

More terms: Clinical Trials and Drug Development

• informed consent
• endpoint
• preclinical