G. O’Neil, G. Hulse, D Arnold-Reed, P. O’Neil, C. Chan, V. Chiera, B. Sunderland, and Y. Liu Australian Medical Procedures Research Foundation, Perth, Australia/ University of Western Australia, Australia/ Go Medical Industries Pty Ltd, Perth, Australia/ Clinipath Laboratories, Perth, Australia/ Curtin University, Australia
There are no established pharmacotherapies available for the treatment of amphetamine, cannabis, or benzodiazepine addiction. The current study, however, indicated that treatment of heroin-dependent persons with a 3.5g - 5g sustained-release naltrexone implant was associated with a decrease in amphetamine, cannabis, or benzodiazepine use over the initial course of treatment while blood naltrexone levels are maintained above 3.8 ng/mL. Data were collected by examining 1,191 urine and blood specimens from 227 patients. Analysis of blood naltrexone levels indicated that naltrexone implants maintained blood levels above 3.8 ± 0.5 ng/mL for approximately 87 days. While the blood level of naltrexone was maintained between 3.8 and 20 ng/mL, there was a steady reduction in the use of benzodiazepines, amphetamines, and cannabis. However, once blood naltrexone levels fell below 3.8 ± 0.5 ng/ml at approximately day 87, the use of benzodiazepines, amphetamines, and cannabis increased (p-value 0.0058, p-value 0.0024, and p-value 0.012, respectively). In contrast, opioid use was reduced over the entire period of treatment observation until day 150. This opioid reduction was associated with significantly lower levels of blood naltrexone to approximately 1ng/ml. It is concluded that naltrexone may have a role in the management of a range of non-opioid drug abuse.