Blood naltrexone and 6-β-naltrexol levels following naltrexone implant: Comparing two naltrexone implants
Hulse, G. K., Arnold-Reed, D. E., O’Neil, G., Chan, C-T., Hansson, R., & O’Neil, P. (2004). Blood naltrexone and 6-β-naltrexol levels following naltrexone implant: comparing two naltrexone implants. Addiction Biology, 9(1), 59-65. doi: 10.1080/13556210410001674103
The aim of this study was to profile and compare blood naltrexone and 6-β-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-βnaltrexol 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-β-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-β-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 heroindependent patient, especially those who find it difficult to shift away from dependent use patterns, are discussed.