title: Blood naltrexone and 6-beta-naltrexol levels following naltrexone implant: comparing two naltrexone implants.
abstract: The aim of this study was to profile and compare blood naltrexone and 6-beta-naltrexol levels with time following treatment with two sustained-release naltrexone preparations produced by GoMedical Industries, Australia at a community heroin treatment clinic in Perth, Western Australia. A sample of 10 patients who each received a 1.7 g naltrexone implant were compared to 24 patients who each received a 3.4 g naltrexone implant as treatment for heroin dependence. Blood naltrexone levels following treatment with the 1.7 g naltrexone implant remained above 2 and 1 ng/ml for approximately 90 and 136 days, respectively. Use of the 3.4 g naltrexone implant extended the period of coverage to approximately 297 (1 ng/ml) or 188 (2 ng/ml) days. Blood 6-beta-naltrexol levels remained above 10 ng/ml for approximately 18 and 83 days, respectively, following use of the 1.7 g and 3.4 g naltrexone implants. The current study data indicate that blood naltrexone and 6-beta-naltrexol levels following treatment with either the 1.7 g or 3.4 g naltrexone implant are greater than those reported in other published data on other sustained-release naltrexone preparations. Furthermore, duration of blood naltrexone and 6-beta-naltrexol levels achieved following use of the 3.4 g implant were superior to those achieved with the 1.7 g naltrexone implant, with naltrexone blood levels maintained above 2 ng/ml for a period of approximately 6.3 months compared to 3 months, respectively. The implications of this in managing the heroin-dependent patient, especially those who find it difficult to shift away from dependent use patterns, are discussed.
authors.affiliation: Unit for Research and Education in Drugs and Alcohol, School of Psychiatry and Clinical Neurosciences, University of Western Australia, Australia. ghulse@cyllene.uwa.edu.au
authors.forename: G K
authors.initials: GK
authors.lastname: Hulse
authors.forename: D E
authors.initials: DE
authors.lastname: Arnold-Reed
authors.forename: G
authors.initials: G
authors.lastname: O'Neil
authors.forename: C-T
authors.initials: CT
authors.lastname: Chan
authors.forename: R
authors.initials: R
authors.lastname: Hansson
authors.forename: P
authors.initials: P
authors.lastname: O'Neil
mesh_terms: D000328:Adult; D015992:Body Mass Index; D003692:Delayed-Action Preparations; D004334:Drug Administration Schedule; D004343:Drug Implants; D005260:Female; D005500:Follow-Up Studies; D006556:Heroin Dependence / Q000097:blood* / Q000188:drug therapy*; D006801:Humans; D008297:Male; D009271:Naltrexone / Q000008:administration & dosage* / Q000031:analogs & derivatives / Q000097:blood* / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000008:administration & dosage* / Q000097:blood* / Q000627:therapeutic use; D012189:Retrospective Studies
chemical_list: D003692:Delayed-Action Preparations; D004343:Drug Implants; D009292:Narcotic Antagonists; D009271:Naltrexone