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Results for “Placebo Effect”

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At least 19 recordsLinked to original sources
PubMed1979

[On circadian variations of the placebo effect on the pain threshold of healthy teeth: Contribution to a physiology of placebo effects (author's transl)].

Placebo doses can influence the pain threshold of healthy teeth according to the label. Systematic longitudinal researches over the day with measuring the utilization time of cold stimulus on healthy front teeth demonstrate that the placebo effect is subject to significant circadian variations. During daytime a pseudo-analgesic causes a stronger and steeper onset of increase of the tooth pain threshold than during the night, when the pain threshold is influenced only minimal or even inverse. The placebo effect can come up to 40% of the pain threshold increase caused by a usual analgesic; this portion, however, is as well subject to high circadian variations. The extent of the placebo effect corresponds to the order of magnitude of the spontaneous circadian variations of pain threshold and correlates positively to it. These correlations are considered as indicating that those vegetative mechanisms causing the circadian variations of the pain threshold are equally involved in affecting the placebo actions.

Circadian Rhythm↗
PubMed1979

The placebo effect.

The most important factors influencing the effects drugs and other therapeutic measures are discussed. i.e. 1) variations between different patients--"individual factors", 2) variations in the environment--"occupational factors", 3) variations in compliance, 4) variations in the spontaneous course of the disease, and 5) variations in the effect of placebo. It is pointed out that "the placebo effect" must always be allowed for when evaluating different methods of treatment.

Clinical Trials as Topic↗
PubMed1978

The placebo effect of transcutaneous electrical stimulation.

The placebo effect of transcutaneous electrical stimulation was studied in 93 patients in a double-blind cross-over trial using a genuine stimulator and a placebo machine. Placebo analgesic effect occurred in 32% of trials, as compared with 48% for actual stimulation. The placebo effect of the transcutaneous electrical stimulator is similar to the placebo effect that is noted in other double-blind studies in which medications are used.

Adult↗
PubMed1978

Situational factors contributing to the placebos effect.

The influence of four variables (status of communicator of drug effects, attitude of dentist, attitude of dental technician, and message of drug effects) on the obtainment of placebo effects in an oral surgery clinic was investigated. Dependent variables were (1) rating of pain experienced from mandibular-block injection, (2) pre-post placebo state anxiety, and (3) pre-postplacebo fear of injection. Enthusiastic messages of drug effects produced statistically and clinically significant reductions in postplacebo fear of injection and state anxiety and markedly lower ratings of pain experienced during injection of local anesthetic. Although there was a strong tendency for positive placebo effects to occur when the dental staff was perceived as friendly and supportive, only the attitude factors obtained statistical significance. The status of the communicator accounted for very small portions of the variance.

Adult↗
PubMed1977

[The placebo effect (author's transl)].

Placebos are liable to affect most diseases, physiologically autonomic and emotional functions and types of performance and also to produce side effects. Types of reactions to placebos are highly dependent on suggestion. Tranquilizer properties are registered more frequently than those of stimulants, and placebos are taken for active drugs more often than vice versa. Type of application, personality of the therapist and intensity of the stress situation may potentiate or diminish the effects of placebos in a specific manner. Constancy of time and situation as a condition for the identification of a placebo reactor is demonstrable to a limited extent only.

Dosage Forms↗
PubMed1979

Placebo response, placebo effect, and two attributes.

Two putative predictors of placebo response were studied in three samples of psychiatric outpatients. Two groups, 73 university medical center patients and 56 college health service patients, underwent 1 week of placebo treatment. A quasi-control group of 112 patients receiving no medication waited about 1 week before beginning psychotherapy. One attribute, acquiescence or traditionalism, predicted placebo response, thereby replicating prior findings. Acquiescence was unrelated to change in controls indicating that it may represent a correlate of true placebo effect under some conditions. Additional findings suggested qualifications as to the generality of the relationship. The second attribute, autonomic awareness, was associated with change in all three samples. It appeared to predict nonspecific improvement unrelated to placebo probably due to its relationship to intensity of somatization.

Adult↗
PubMed1978

Placebo effect in the treatment of angina pectoris.

The interference of placebo effect in the treatment of angina pectoris has been studied in a group of patients with stable angina pectoris, selected on the basis of normal electrocardiogram at rest and a pathologic ergometric electrocardiographic test. It was found that the patients could be divided, according to the results of the exercise test, into two groups: placebo responders and place-bo-non-responders. The anti-anginal effect of beta-blocking agents has been clearly demonstrated only in the placebo-non-responders group. No statistically significant effect of beta-blocking agents was observed in the placebo-responders group. This result shows that it is necessary, in double blind trials, at first to separate placebo-responders from placebo-non responders. Otherwise the correct evaluation of a drug can be modified by the placebo-responders group.

Adult↗
PubMed1977

The placebo effect. Is it important in diverticular disease?

Thirty patients with diverticular disease confirmed by barium enema examination were entered into a three-month double-blind trial of two tablets of methylcellulose (Celevac) daily or two placebo tablets daily. As these tablets were indistinguishable it was possible to cross over nine of the patients and follow them for a further three-month period. The placebo effect was sufficient for 11 patients who completed the trial on placebo to show a small mean improvement. A greater mean clinical improvement was shown, however, by the 16 patients who completed the trial on methylcellulose and in those who were crossed over, most of the improvement occurred during the time the patients were on methylcellulose.

Aged↗
PubMed1979

Paracetamol versus placebo: effects on post-operative course.

Paracetamol was compared with placebo in a double-blind crossover study, in which essentially the same operation was performed on two separate occasions in 24 healthy patients, namely surgical removal of bilateral impacted wisdom teeth. Commencing on the day of surgery, either paracetamol (Panodil; 1.0 g x 4 for 2 days, then 0.5 g x 4 for the next 2 days) or placebo tablets were given, followed by crossover to the alternative treatment at the second operation about 4 weeks later. Several objective and subjective assessments were recorded for paired comparison of post-operative courses. Swelling on the 3rd day after operation when paracetamol was given averaged 71% of that measured when placebo was given (p less than 0.05). After paracetamol, a tendency was noted towards reduced local hyperpyrexia and less post-operative bleeding. The pain and preference scores were clearly in favour of paracetamol. The results provide evidence to suggest that paracetamol may reduce an acute, posttraumatic inflammatory reaction.

Acetaminophen↗
PubMed1979

Peer interaction in a structured communication task: comparisons of normal and hyperactive boys and of methylphenidate (Ritalin) and placebo effects.

Peer communication patterns were assessed as school-aged boys participated in a dyadic referential communication task. The responses of comparison boys were compared to those of hyperactive boys on methylphenidate (Ritalin) and on placebo in a double-blind crossover design. 2 separate systems for assessing communication were developed, a qualitative system designed to capture the "flavor" of interaction and a quantitative system focused on specific types of communicative content. Task products and completion times were also scored. The results suggest that hyperactive children, regardless of medication status, are less likely than comparison peers to (a) modulate ongoing or habitual behavior patterns in response to externally imposed shifts in role-appropriate behaviors; (b) maintain consistent, uninterrupted goal orientation; and (c) respond to subtle social learning opportunities. In this situation, methylphenidate appeared to have a greater impact on behavioral style than on competence, decreasing perceived intensity without influencing efficiency. A mild medication-induced dysphoria was also documented. Directions for future research and the need for caution in clinical interpretation are discussed.

Affect↗