Harmen Beurmanjer

66 Chapter 5 over BZD treatment, due to its pharmacological similarity with street GHB. BZD mainly act at GABA-A receptors, whereas GHB mainly acts at GHB and GABA-B receptors. BZDs might therefore be less effective in supressing GHB withdrawal because they target different receptors to GHB. A disadvantage of GHB tapering is its shorter half-life, requiring GHB administration throughout the night which interferes with sleep. Continued GHB use could also be seen as reinforcing compulsive substance use, potentially maintaining symptoms, such as craving (Kwako & Koob, 2017). While both methods are currently in use, studies comparing both methods are not available. This study aimed to indirectly compare these two tapering methods for the detoxification of GHB in patients with GUD. In Belgium physicians are not allowed to prescribed pharmaceutical GHB for GHB withdrawal and BZD tapering is the standard of care. In the Netherlands, tapering with pharmaceutical GHB detoxification is the preferred option, based on the existing literature and national guidelines. Therefore, the current study made a matched comparison between the two treatments-as-usual in each country. Based on current literature and the pharmacological profile of GHB, it is expected that the pharmaceutical GHB tapering has 1) a less severe withdrawal syndrome, 2) fewer adverse events, and 3) higher craving levels during the detoxification process in patients with GUD, compared to the tapering with BZD. Methods Study Design The study was a multicentre non-randomized indirect comparison of two treatments of usual, comparing the effectiveness between BZD tapering in Belgium and GHB tapering in the Netherlands in patients with GUD. Ethical approval for the Belgian part was obtained from the Institutional Review Board ZNA/OCMW Antwerpen (E.C. Approval N° 4664). For theDutch part, theMedical Ethical ResearchCommittee Twente andCentral Committee on Research Involving Human Subjects (CCMO) approved the pharmaceutical GHB protocol andconsidered that the studydidnot fall under the scopeof theMedical Research Involving Human Subjects Act (WMO). The data from this study was published in 2017 (Dijkstra et al., 2017) and a sample from this dataset is used in the current study. Off-label use of pharmaceutical GHB for GHB detoxification was approved by the Dutch Health care Inspection and is now considered the standard detoxification treatment for patients with GUD in the Netherlands. The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national and institutional committees on human experimentation and with the Helsinki Declaration of 1975, as revised in 2008. All procedures involving human patients were approved by the above mentioned boards and committees.