Effect of buspirone on thermal sensory and pain thresholds in human volunteers.
BACKGROUND
Buspirone is a partial 5-HT1A receptor agonist. Animal studies have shown that modulation of serotoninergic transmission at the 5-HT1A receptor can induce analgesia in acute pain models. However, no studies have been published so far on the effects of serotonin receptor agonists on pain perception in humans.


METHODS
The effects of buspirone (30 mg p.o.) on thermal sensory and pain thresholds were investigated in twelve female volunteers (26 +/- 2 yrs) in a prospective, randomized, double-blind, double-dummy, placebo-controlled study with morphine (10 mg i.v.) as positive control.


RESULTS
Morphine significantly increased the heat pain detection threshold (DeltaT: placebo 1.0 degrees C and 1.3 degrees C, p < 0.05) at 60 minutes. Buspirone caused mild sedation in six participants at 60 minutes, but was without effect on any of the measured parameters.


CONCLUSIONS
Buspirone in the maximal recommended dose was without significant effect on thermal pain. However, as it is only a partial agonist at the 5-HT1A receptor and also acts on other receptor types, the negative results of the present study do not rule out a possible analgesic effect of more specific 5-HT1A receptor agonists.
Pavlaković
Goran
G
Department of Anesthesiology, Emergency and Intensive Care Medicine, University of Göttingen Medical School, Göttingen, Germany. pavlakovic@gmx.net
Tigges
Julija
J
Crozier
Thomas A
TA
D000328:Adult; D000701:Analgesics, Opioid / Q000378:metabolism; D002065:Buspirone / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D006358:Hot Temperature; D006805:Human Experimentation; D006801:Humans; D009020:Morphine / Q000378:metabolism*; D017288:Pain Threshold / Q000187:drug effects*; D010919:Placebos / Q000494:pharmacology; D012684:Sensory Thresholds / Q000187:drug effects* / Q000502:physiology; D058825:Serotonin 5-HT1 Receptor Agonists; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*
D000701:Analgesics, Opioid; D010919:Placebos; D058825:Serotonin 5-HT1 Receptor Agonists; D017366:Serotonin Receptor Agonists; D009020:Morphine; D002065:Buspirone