Opiate antagonism fails to reverse hypnotic-induced analgesia

Mechanism of analgesia induced by hypnosis and acupuncture: is there a difference?

Hypnosis and acupuncture can alleviate experimentally induced pain but the mechanism of analgesia remains unclear for both techniques. Experimental pain was induced by cold pressor test (CPT) in 8 male volunteers. Analgesic effect of hypnosis (HA) and acupuncture (AA) was assessed before and after double-blind administration of placebo or naloxone, in a prospective, cross-over study. We found that pain intensity was significantly lower with HA as compared with AA, both with naloxone (P less than 0.001) and placebo (P less than 0.001). Within HA or AA groups, pain scores did not differ significantly when naloxone or placebo was administered. During AA, however, pain scores were similar to control values when naloxone was given (P = 0.05) but decreased significantly with placebo (P less than 0.002). Analog scales for pain intensity and pain relief showed a good correlation (r = 0.94). Plasma levels of beta-endorphins did not change significantly in any combination. Heart rate, peripheral arterial blood pressure and skin conductance were very insensitive indices to assess pain intensity or relief, as well as intensity of acupuncture stimulation or depth of hypnotic trance. We conclude: (1) HA and AA can significantly reduce pain from CPT, and HA is more effective than AA: (2) HA and AA are not primarily mediated by the opiate endorphin system; and (3) plasmatic levels of beta-endorphins are not significantly affected by either HA or AA nor by naloxone or placebo administration.

Hypnotic versus active cognitive strategies for alleviation of procedural distress in pediatric oncology patients

This study provided a differential comparison of the efficacy of standardized instruction in hypnosis or active cognitive strategy for provision of relief from procedurally induced pain and anxiety. Subjects were instructed to self-direct in the use of strategies during medical procedures. Twenty pediatric oncology patients participated in the study. They were not informed that hypnosis was one of the strategies. Subjects were screened for hypnotizability and randomly assigned to treatments. Demographic data were collected. Pre-strategy training observations were made during a Bone Marrow Aspiration or Lumbar Puncture (BMA/LP) using visual analog scales, the McGill Pain Questionnaire, State-Trait Anxiety Inventory, pulse and temperature readings, and interview. Following strategy training, data were collected during a second BMA/LP using the same measures as employed pre-intervention. Results indicated that both strategies were effective in providing pain reduction. Neither technique provided for anxiety reduction. Hypnotizability scale scores failed to correlate with degree of pain reduction.

Naloxone fails to reverse hypnotic alleviation of chronic pain

The hypothesis that the alleviation of chronic pain with hypnosis is mediated by endorphins was tested. Six patients with chronic pain secondary to peripheral nerve irritation were taught to control the pain utilizing self-hypnosis. Each subject was tested at 5-min intervals during four 1-h sessions for the amount of reduction of pain sensation and suffering associated with hypnosis while being given, in a random double-blind crossover fashion, an IV injection of either 10 mg naloxone or a saline placebo through an indwelling catheter. The patients demonstrated significant alleviation of the pain with hypnosis, but this effect was not significantly diminished in the naloxone condition. These findings contradict the hypothesis that endorphins are involved in hypnotic analgesia.