Suboxone (buprenorphine + naloxone)

• combination buprenorphine and naloxone was introduced to help eliminate diversion and IV use of buprenorphine (1)
  • combination is supposed to have a lower IV abuse potential than buprenorphine alone
    • sublingual tablet combining buprenorphine and naloxone in a 4:1 ratio (Suboxone) has been developed (2)
      • taken as directed (sublingually), the naloxone component is not clinically active and so Suboxone is as efficacious as buprenorphine alone (3,4)
      • when injected the naloxone is clinically active and is likely to precipitate withdrawal in opioid-dependent patients (3)
    • however a survey of IV drug abusers revealed that 68% of the respondents had tried IV buprenorphine + naloxone and 66% of those who tried it, took it again or even regularly (1)
      • may indicate that combining naloxone with buprenorphine does not block all agonist effects when used IV
      • however, the continued usage of the combination product might reflect the fact that the study population was from a needle exchange program accustomed to using drugs IV, and the habit may not have been extinguished by a few non-reinforced attempts
        • this conclusion is supported by the finding that 80% reported that they had a 'bad' experience with the combination product, while less than 20% reported it 'similar' to experiences with IV buprenorphine
        • consistent with this finding, respondents were willing to pay a significantly higher street price for buprenorphine than for the combination product
      • the study authors concluded that treating heroin misuse with the combination buprenorphine + naloxone, could reduce the number using buprenorphine IV on the street (1)

Reference:

1. Alho H et al. Abuse liability of buprenorphine-naloxone tablets in untreated IV drug users. Drug Alcohol Depend. 2006.
2. Bell J et al. A pilot study of buprenorphine-naloxone combination tablet (Suboxone) in treatment of opioid dependence.Drug Alcohol Rev. 2004 Sep;23(3):311-7.
3. Mendelson et al. Drug Alcohol Depend 2003;70:29-37.
4. Fudula et al. New Engl J Med 2003;349:949-95.