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

/pla·ce·bo/ (plah-se´bo) [L.] any dummy medical treatment; originally, a medicinal preparation having no specific pharmacological activity against the patient's illness or complaint given solely for the psychophysiological effects of the treatment; more recently, a dummy treatment administered to the control group in a controlled clinical trial in order that the specific and nonspecific effects of the experimental treatment can be distinguished.

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

[pləsē′bō]
Etymology: L, shall please
an inactive substance, such as saline solution, distilled water, or sugar, or a less than effective dose of a harmless substance, such as a water-soluble vitamin, prescribed as if it were an effective dose of a needed medication. Placebos are used in experimental drug studies to compare the effects of the inactive substance with those of the experimental drug. They are also prescribed for patients who cannot be given the medication they request or who, in the judgment of the health care provider, do not need that medication.

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

harmless inert substance given as medicine or supplement. In a randomized placebo-controlled trial, this is identical in appearance with the active material being tested. When neither the researcher nor the subjects know which is which, the trial is said to be 'double blind'. placebo effect a therapeutic effect or in the case of sport performance an enhancing effect observed after the administration of a placebo.

placebo

inert substance, identical in all other respects to an experimental compound under test

placebo (pl·sēˑ·bō),

n 1. inert substance used in control groups of clinical studies to maintain blinding.
2. beneficial effects of the meaning and context of treatment independent of the treatment itself. See also meaning effect.
placebo effect,
n 1. the effect of any therapeutic technique that has no objectively determinable action on the illness for which it is prescribed.
2. the patient's innate healing, defense and survival processes that are elicited through the meaning and context of a treatment.
placebo response,
n changes in a patient's condition from the meaning and context of the treatment and not from an active agent.
placebo sag,
n the reduction in the efficacy of a particular placebo therapy due to prolonged absence of an active stimulus.
placebo therapeutics,
n.pl treatments in which a physician attempts to engage the patient's own healing processes by prescribing physiologically inactive stimuli.

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]

placebo (pləsēbō),

n a substance that resembles medicine superficially and is believed by the patient to be medicine but that has no intrinsic drug activity.
placebo effect,
n the real or imagined effect of a placebo, which may actually be the same effect ordinarily associated with the administration of a therapeutically active agent.

placebo

[L.] a substance given to a patient as medicine or a procedure performed on a patient that has no intrinsic therapeutic value but pleases the patient's owner who expects to have to give the animal some medicine. A placebo may be administered in the form of a sugar pill or an injection of sterile water.
Placebos are also used in controlled clinical trials of new drugs. While some patients selected at random are given the new drug, others are given a placebo. Often this is an active placebo that mimics the new drug's side-effects. Neither the patients nor the veterinarians know who is receiving the real drug. The patients taking the new drug must have significantly more relief of signs than the control group taking the placebo for the new drug to be considered to be effective. Placebos can produce an effect that is either positive, with improvement of signs, or negative, with worsening of signs or the appearance of adverse side-effects.
References in periodicals archive ?
Only members of the research team not involved in providing day-to-day clinical care will know which patients are receiving an active treatment or a placebo.
In less than five minutes, in which the previously unknown concept of a placebo was briefly mentioned, the session was over, and Ouattara, unemployed and illiterate, had agreed to take part in the tests.
Antonuccio of the University of Nevada School of Medicine in Reno also stresses placebo power.
At week 16, all placebo patients were randomized to either the 100 or 200 mg dose of Reverset and study physicians were again given the option to reoptimize the background therapy of any patient if appropriate.
11,000 heart attack survivors take omega-3 fats (1 gram), vitamin E (670 IU), both, or a placebo daily for 4 years.
What both John and Susan are experiencing, in different ways, are aspects of the placebo effect: it can help people feel "physically better" for a time; it can be used to help a person with a disease like MS develop a positive mental attitude; it can be a necessary component in the determination of a clinical trials efficacy; at the same time, it can confuse the evaluation of new therapies and complicate the design of clinical studies.
In one, 21 of 24 men with erectile dysfunction who took ArginMax for four weeks reported improvement in their ability to maintain an erection during intercourse, compared to five of 24 men who were given a placebo.
3 percentage point mean increase in pulmonary capacity as measured by FVC compared to patients treated with placebo (p=0.
The researchers studied 17 men, all hospitalized for major depression, who received either Prozac or a placebo for 6 weeks.
Evidence: In the best study on black cohosh root, 30 women who took Remifemin for 12 weeks reported far fewer hot flashes and other symptoms than 20 similar women who were given a placebo.
Patients were randomized to receive placebo or BG-12 at 120 mg, 360 mg, or 720 mg per day orally for six months.