title: Effect of local administration of transdermal fentanyl on peripheral opioid analgesia.
abstract: OBJECTIVE
  Transdermal fentanyl is a commonly used analgesic for the treatment of severe chronic pain. Recent investigations have shown the presence of mu-opioid receptors in the skin and opioid analgesic efficacy with alternative routes of administration of narcotics. This placebo-controlled, double-blind prospective study assessed whether transdermal fentanyl administration produces local peripheral opioid analgesia at the site of application.
  
  
  METHODS
  Baseline pain threshold and supra-threshold pain intensity assessments were measured using Quantitative Sensory Testing in 12 healthy volunteers. Placebo and fentanyl containing patches (Duragesic, 25 microg/h) were applied to opposite forearms for 2 h. After patch removal, pain threshold, supra-threshold pain response, and the area of secondary hyperalgesia were evaluated for both forearms.
  
  
  RESULTS
  No statistically significant differences in pain threshold, supra-threshold pain intensity, or area of hyperalgesia in fentanyl- versus placebo-treated forearms were detected in the study subjects.
  
  
  CONCLUSIONS
  These results suggest that the application of transdermal fentanyl patch for a period of 2 h does not produce local peripheral opioid analgesia at the site of patch application.
authors.affiliation: Department of Anesthesiology, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Worrich
authors.forename: Gregg
authors.initials: G
authors.lastname: Schuler
authors.forename: Piotr K
authors.initials: PK
authors.lastname: Janicki
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000097:blood; D004311:Double-Blind Method; D005283:Fentanyl / Q000008:administration & dosage* / Q000097:blood; D006801:Humans; D006930:Hyperalgesia / Q000139:chemically induced; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects*; D010919:Placebos; D014110:Touch
chemical_list: D000701:Analgesics, Opioid; D010919:Placebos; D005283:Fentanyl