Abstract |
The analgesic activity of an opiate was studied in 12 healthy volunteers using a cold-induced pain (CP) model. Effects on the central nervous system (CNS) were also measured. According to a double-blind, randomised, balanced, cross-over design with an interval of 7 days between occasions, subjects received single oral doses of 2, 4 and 8 mg dipipanone (D2, D4, D8) and a placebo. The CP test and a battery of measurements of CNS function were performed 3 times on each study day, once before and again 1.5 h and 3.0 h after treatment. Mean pain cores on a computerised visual analogue scale were significantly higher after placebo than those after 4 mg (P less than 0.05) and 8 mg (P less than 0.01) dipipanone and a dose-response relationship was evident. The opiate did not affect baseline blood pressure before the CP test but the hypertensive response to the painful cold stimulus was diminished 3 h after D8. Scores on scales for subjective assessment of alertness were significantly reduced 3 h after the 8 mg dose and pupil diameters were significantly smaller after all 3 doses of dipipanone. Body sway and visual near points were not significantly altered by the opiate. It is concluded that the CP test is a sensitive model for measurement of opiate-induced analgesia in healthy volunteers. Pupillometry and visual analogue scales are useful for the assessment of central effects of opiates.
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Authors | John Posner, Andras Telekes, Dominic Crowley, Richard Phillipson, Anthony W Peck |
Journal | Pain
(Pain)
Vol. 23
Issue 1
Pg. 73-82
(Sep 1985)
ISSN: 0304-3959 [Print] United States |
PMID | 2865712
(Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial)
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Chemical References |
- Analgesics, Opioid
- Methadone
- dipipanone
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Topics |
- Adult
- Analgesics, Opioid
(pharmacology)
- Blood Pressure
(drug effects)
- Central Nervous System
(drug effects)
- Cold Temperature
(adverse effects)
- Dose-Response Relationship, Drug
- Double-Blind Method
- Female
- Humans
- Male
- Methadone
(analogs & derivatives, pharmacology)
- Pain
(physiopathology)
- Random Allocation
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