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 ?
Yet, larger placebo responses in chronic pain were found in responders with more negative treatment history [74], indicating that prior experience plays an important moderating role, which, however, could be mediated by expectations.
This is an interesting study that demonstrates the potential benefit of harnessing placebo responses to elicit positive outcomes in patients.
Researchers are often faced with a dilemma: Is the drug a failure or is the placebo response too great to see the drug response?
It is the opposite of the placebo response. Specifically, people have an expectation that they will have a negative health effect and then a negative effect actually occurs.
What is generally perceived as the placebo response is not necessarily response to placebo.
"This Phase III trial builds on the signals of efficacy observed in our earlier PDP studies and uses a refined study design that we expect will help mitigate the placebo response, reduce variability and enhance sensitivity in measuring the efficacy of pimavanserin in PDP patients," said Uli Hacksell, PhD, Chief Executive Officer of ACADIA.
The placebo response has drug manufacturers flummoxed, according to an article for Wired magazine by Steve Silberman.
Placebo response in depression: bane of research, boon to therapy (Editorial).
In late March, Osiris announced it has elected to end enrollment at 210 patients in its Phase III trial evaluating Prochymal for Crohn's disease because it believes there is a design flaw in the trial resulting in significantly higher than expected placebo response rates.
But the placebo response strongly depends upon the beliefs of the patient.
We also know that the most important part of this placebo response is the belief of our doctors - when our doctors firmly believe in our medicines, our own belief is enhanced, and that makes the drugs more healing, regardless of the content of the medicines.