placebo


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placebo

 [plah-se´bo] (L.)
1. a supposedly inert substance such as a sugar pill or injection of sterile water, given under the guise of effective treatment. Paradoxically, it may exert either a positive or a negative effect on the recipient (see placebo effect). A positive placebo effect can occur when caregiver and patient believe and expect a medication or procedure will relieve symptoms. Placebos are sometimes used in controlled clinical trials of new drugs; while some patients selected at random are given the new drug, others are given a placebo. It may be an active placebo that mimics the new drug's side effects. The patients taking the new drug must have significantly more relief of symptoms than the control group taking the placebo for the new drug to be considered to be effective. See also single blind, double blind, and triple blind.
2. the term has been extended to mean virtually any type of ineffective treatment, including surgery and psychotherapy. Use of placebos is ethically problematic because it deceives the patient. Ethical questions regarding the use of placebos include: (1) Is deception necessary to produce benefit? and (2) Do placebos have a nondeceptive use?

pla·ce·bo

(plă-sē'bō),
1. An inert substance given as a medicine for its suggestive effect.
2. An inert compound identical in appearance to material being tested in experimental research, which may or may not be known to the physician or patient, administered to distinguish between drug action and suggestive effect of the material under study.
Synonym(s): active placebo
[L. I will please, future of placeo]

placebo

(plə-sē′bō)
n. pl. place·bos or place·boes
a. A substance that has positive effects as a result of a patient's perception that it is beneficial rather than as a result of a causative ingredient.
b. An inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug.

placebo

An inactive material, often in the form of a capsule, pill or tablet, that is visually identical in appearance to a drug being tested in a clinical trial. The use of placebo control is a required component of the FDA’s drug approval process, as the agent must be proven more effective than the placebo.

Ethical questions are sometimes raised about certain uses of placebo controls, as when a negative or placebo control is required to evaluate the efficacy of a therapeutic manoeuvre (thereby denying the placebo group of the therapy’s potential benefit).

placebo

Medtalk An inactive material, in the form of a capsule, pill, or tablet, which is visually identical, and administered by the same route as a drug being tested; a chemically inert substance given in the guise of medicine for its psychologically suggestive effect; used in controlled clinical trials to determine whether improvement and side effects may reflect imagination or anticipation rather than the drug's power. See Dose control trial, Equivalence trial, Putative placebo trial. Cf Nocebo.

pla·ce·bo

(plă-sē'bō)
1. A medicinally inactive substance given as a medicine for its suggestive effect.
2. An inert compound identical in appearance to material being tested in experimental research, which may or may not be known to the physician or patient, administered to distinguish between drug action and suggestive effect of the material under study.
3. Any treatment or intervention with no intrinsic therapeutic value performed to achieve a "placebo effect."
[L. I will please, future of placeo]

placebo

1. A pharmacologically inactive substance made up in a form apparently identical to an active drug that is under trial. Both the placebo and the active drug are given, but the subjects are unaware which is which. This is done for the purpose of eliminating effects due to purely psychological causes.
2. A harmless preparation prescribed to satisfy a patient who does not require active medication. From the Latin placere, to please. See also PLACEBO EFFECT.

placebo

  1. any inactive substance given to satisfy a patient's psychological need for medication.
  2. a control in an experiment to test the effect of a drug.

Placebo

An inactive substance with no pharmacological action that is administered to some patients in clinical trials to determine the relative effectiveness of another drug administered to a second group of patients.

placebo 

A substance or a prescription (e.g. plano lenses) devoid of any physiological effect that is given merely to satisfy a patient. It is also used in research as a control against which the real effect of another product (similar in appearance) can be established. See single-blind study; randomized controlled trial.

pla·ce·bo

(plă-sē'bō)
Inert substance given as a medicine for its suggestive effect.
Synonym(s): active placebo.
[L. I will please, future of placeo]
References in periodicals archive ?
She was given a placebo pill which was clearly labeled on the bottle, and doctors told her there were no active ingredients in the pills.
Previous research on the mechanisms of placebo and nocebo effects might be biased due to a number of reasons: (1) studies that investigate the effects of conditioning without verbal suggestion are scarce [30, 36, 37].
The idea that the treatment situation itself provides reassurance and reduces distress, and in doing so, powers a good bit of the placebo effect, is enshrined in such concepts as the importance of good bedside manner.
Soon Randomized controlled trial became the standard of medical research and placebo became its integral component.
This brings to mind Ted Kaptchuk's somewhat mind boggling study from 2010 on placebo effect in irritable bowel syndrome (IBS) that suggested it doesn't matter what patients know.
The results showed greater reductions in pain for patients assigned to placebo. On a 0-to-10 scale, patients in the placebo group had a 1.5-point improvement in pain score, compared to no significant change for patients taking usual medications only.
In psychiatry, anxiety is the most respondent symptom to the placebo effect, which has led some authors to argue that "placebo is one of the best known anxiolytic", although Rickels (1971), as other authors, have pointed out, states the number cases in which the pharmacologically active products are anxiolytics is three--four times higher.
Ted Kaptchuk's work differed from the traditional placebo effect, in that he told the patients that the pill they were receiving was not truly medicine.
Large-scale genome studies run in conjunction with clinical drug trials could help fill in the gaps in understanding which genes are involved and what role they play in boosting the placebo effect.
Conclusion This study showed that cimetidine is not more effective than placebo in treatment of warts.
(The "double-blind" part refers to the fact that in addition to having both a placebo group and a treatment group, neither the researchers nor the subjects know which subjects receive the treatment and which receive the placebo until the trial is concluded.)
The placebo effect has been the subject of frequent research in human medicine, with results ranging from the psychological--you expect to feel better taking a medicine and you do--to the physiological--endorphins in the brain and spinal fluid caused your improvement.