title: Acute effects of intramuscular and sublingual buprenorphine and buprenorphine/naloxone in non-dependent opioid abusers.
abstract: BACKGROUND
  Buprenorphine is a partial mu opioid receptor agonist with clinical efficacy as a pharmacotherapy for opioid dependence. A sublingual combination formulation was developed containing buprenorphine and naloxone with the intent of decreasing abuse liability in opioid-dependent individuals. However, the addition of naloxone may not limit abuse potential of this medication when taken by individuals without opioid physical dependence.
  
  
  OBJECTIVE
  The present study investigated the effects of buprenorphine alone and in combination with naloxone administered intramuscularly and sublingually to non-dependent opioid abusers.
  
  
  METHODS
  In a within-subject crossover design, non-dependent opioid-experienced volunteers (N = 8) were administered acute doses of buprenorphine (4, 8, and 16 mg) and buprenorphine/naloxone (4/1, 8/2, and 16/4 mg) via both intramuscular and sublingual routes, intramuscular hydromorphone (2 and 4 mg as an opioid agonist control), and placebo, for a total of 15 drug conditions. Laboratory sessions were conducted twice per week using a double-blind, double-dummy design.
  
  
  RESULTS
  Buprenorphine and buprenorphine/naloxone engendered effects similar to hydromorphone. Intramuscular administration produced a greater magnitude of effects compared to the sublingual route at the intermediate dose of buprenorphine and at both the low and high doses of the buprenorphine/naloxone combination. The addition of naloxone did not significantly alter the effects of buprenorphine.
  
  
  CONCLUSIONS
  These results suggest that buprenorphine and buprenorphine/naloxone have similar abuse potential in non-dependent opioid abusers, and that the addition of naloxone at these doses and in this dose ratio confers no evident advantage for decreasing the abuse potential of intramuscular or sublingual buprenorphine in this population.
authors.affiliation: Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, 5510 Nathan Shock Drive, Baltimore, MD 21224, USA.
authors.forename: Angela N
authors.initials: AN
authors.lastname: Duke
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Correia
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Walsh
authors.forename: George E
authors.initials: GE
authors.lastname: Bigelow
authors.forename: Eric C
authors.initials: EC
authors.lastname: Strain
mesh_terms: D000286:Administration, Sublingual; D000328:Adult; D002047:Buprenorphine / Q000008:administration & dosage* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004338:Drug Combinations; D055030:Drug Users / Q000523:psychology*; D005260:Female; D006801:Humans; D004091:Hydromorphone / Q000008:administration & dosage / Q000494:pharmacology; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D009270:Naloxone / Q000008:administration & dosage* / Q000494:pharmacology; D009293:Opioid-Related Disorders / Q000517:prevention & control*; D011795:Surveys and Questionnaires
chemical_list: D004338:Drug Combinations; D009270:Naloxone; D002047:Buprenorphine; D004091:Hydromorphone