author={JonD. Levine and Newton C. Gordon and Howard L Fields},
  journal={The Lancet},
Placebo and naloxone can alter post-surgical pain by separate mechanisms
Evidence is reported that placebo analgesia can occur after blockade of opioid mechanisms by naloxone and that n aloxone can produce hyperalgesia independent of the placebo effect.
Naltrexone during pain conditioning: A double-blind placebo-controlled experimental trial
The results point to the possibility that associative learning, and conditional responding to pain cues, is not dependent on endogenous opioids, as well as demonstrating comparable learning of pain responses in participants treated with naltrexone or inert pill.
Endogenous opiates and the placebo effect: a meta-analytic review.
Effects of naloxone on post-operative pain and steroid-induced analgesia.
Present and previous results in this model with bilateral oral surgery suggest that short term corticosteroid administration deserves attention as an efficient means which may be of value in reducing pain and excessive inflammation in surgery and traumatology.
The true size of placebo analgesia: Concordant neural and behavioural measures of placebo analgesia during experimental acute pain
A robust estimate of the neural and behavioural measures of placebo analgesia is provided by contrasting the effect of pain relief expectation from an inert cream (vaseline) against a real topical analgesic agent (lidocaine) applied on two different limbs and their respective control conditions.
Lower Placebo Responses After Long-Term Exposure to Fibromyalgia Pain.
  • E. Kosek, A. Rosén, K. Jensen
  • Medicine, Psychology
    The journal of pain : official journal of the American Pain Society
  • 2017
Mechanisms of the placebo response in pain in osteoarthritis.


A study of the placebo response.
Naloxone alters pain perception and somatosensory evoked potentials in normal subjects
Results suggest that individual differences in pain sensitivity may relate to differences in an endorphin system, and naloxone administered to man should alter pain appreciation.
Lack of effect of naloxone on pain perception in humans
The experiments reported here demonstrate that the perception of experimentally induced pain in normal human subjects is not altered by administration of the opiate antagonist naloxone.
Pain relief by electrical stimulation of the central gray matter in humans and its reversal by naloxone.
The results suggest that satisfactory alleviation of persistent pain in humans may be obtained by electronic stimulation.
The narcotic antagonist naloxone enhances clinical pain
It is demonstrated here that following the extraction of impacted wisdom teeth, naloxone causes a significantly greater increase in reported pain intensity than placebo, an observation consistent with the suggested participation of endorphins in an intrinsic pain suppression system.
Naloxone treatment of opiate dependence. A progress report.
The duration of action of naloxone hydrochloride, a narcotic antagonist, was extended by increasing doses in nine male volunteers by measuring blockade against intravenously administered heroin challenges and no toxic symptoms occurred.
The powerful placebo.
  • H. Beecher
  • Medicine
    Journal of the American Medical Association
  • 1955
It is interesting that Pepper could say as recently as 10 years ago "apparently there has never been a paper published discussing the important subject of the placebo," but in 1953 Gaddum1 said: Such tablets are sometimes called placebos, but it is better to call them dummies.
Dependence on a placebo: a case report.
  • O. Vinař
  • Medicine
    The British journal of psychiatry : the journal of mental science
  • 1969
There is ample evidence that placebo can cause most, if not all, of the effects due to any active drug (Beecher, 1962; Honigfeld, 1964). A detailed case history of apparent dependence on a placebo
beta-Endorphin and adrenocorticotropin are selected concomitantly by the pituitary gland.
Both hormones possess common and identical regulatory mechanisms and there may be a functional role for circulating beta-endorphin in response to acute stress or long-term adrenalectomy.