Treatment of Opioid Dependence With Buprenorphine/Naloxone After Liver Transplantation: Report of Two Cases E. Aldemir a, *, H. Coskunol a , M. Kilic b , and I. Sert c a Ege University, Institute on Drug Abuse, Toxicology and Pharmaceutical Science, Izmir, Turkey; b Department of Liver Transplantation, Kent Private Hospital, Izmir, Turkey; and c Department of Organ Transplantation, Tepecik Training and Research Hospital, Izmir, Turkey ABSTRACT Opioid dependence is an increasing public health problem. One of the complications of intravenous opioid use is hepatitis C virus infection, which, in turn, is one of the most common indications for liver transplantations throughout the world. Therefore, the treatment of opioid dependence in a liver transplant recipient requires special attention in terms of graft function, drug interactions, and patient compliance. Buprenorphine is a semi-synthetic opioid-derived agent with analgesic effects. To prevent buprenorphine abuse, it is combined with the opioid antagonist naloxone. This buprenorphine/naloxone combination is the only drug approved for the treatment of opioid dependence in Turkey. Although the literature includes data about the safe usage of buprenorphine in liver transplantation in animals, there is no such evidence in either case reports or clinical trials for the same in humans. In this article, we present a report of our treatment of 2 opioid- dependent patients with buprenorphine/naloxone after liver transplantation due to hepatitis C viruseinduced liver cirrhosis. O PIOID dependence is a public health problem that has increasingly become more widespread in Turkey and all over the world [1,2]. With the increase in its prevalence, social, psychiatric, and medical problems associated with opioid use are also on the rise [2]. One of the most important medical problems associated with the intravenous use of opioids is hepatitis C virus (HCV) infection. Of individuals who use substances intra- venously, 60%e90% become infected with HCV and it is now one of the principal reasons for liver transplantations in the United States and Europe [3]. The pharmacological agent used most commonly in the treatment of opioid dependence is methadone [4]. Metha- done is a synthetic opioid agonist. There is data suggesting that the use of methadone is safe in the preoperative and postoperative period in patients undergoing liver trans- plantation [5e7]. However, methadone has still not been approved for use in Turkey. Another agent used commonly in the treatment of opioid dependence is buprenorphine: a semi-synthetic opioid derivative exerting partial agonist effects on mu-opioid receptors and antagonistic effects on kappa- opioid receptors. As an effective analgesic, which is 25- to 40-fold more potent then morphine [8], it has been reported to be a useful agent in decreasing perioperative pain [9]. Buprenorphine is combined with the opioid antagonist naloxone to prevent misuse in opioid- dependent patients because, although naloxone has almost no effect when used sublingually, it exerts antagonistic effects if misused intravenously [1]. In Turkey, the combination of buprenorphine/naloxone was approved for the treatment of opioid dependence by the Ministry of Health in 2010. However, as far as we know, there are no reports in the literature suggesting that it can be used safely in patients undergoing liver trans- plantation. On the contrary, there are case reports stat- ing that its use within therapeutic dose range can result in severe hepatotoxicity [3]. In this article, we describe our treatment of 2 opioid- dependent patients with buprenorphine/naloxone after liver transplantation due to HCV-induced cirrhosis. *Address correspondence to Ebru Aldemir, MD, Ege Univer- sity, Institute on Drug Abuse, Toxicology and Pharmaceutical Science, 35100 Izmir, Turkey. E-mail: ozturk.ebru2000@gmail. com ª 2016 Elsevier Inc. All rights reserved. 230 Park Avenue, New York, NY 10169 0041-1345/16 http://dx.doi.org/10.1016/j.transproceed.2016.08.005 Transplantation Proceedings, 48, 2769e2772 (2016) 2769