Open-Label Study of a Proprietary Treatment Program Targeting Type A γ-Aminobutyric Acid Receptor Dysregulation in Methamphetamine Dependence

Abstract

To evaluate the safety and efficacy of the pharmacological component of a proprietary medical treatment program targeting type A gamma-aminobutyric acid receptor dysregulation in adults who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for methamphetamine dependence. A prospective, open-label, single-group study of the medication portion of a proprietary treatment program for methamphetamine dependence was conducted from July 1, 2005, to May 10, 2006, at Research Across America, an outpatient private, for-profit, clinical research company in Dallas, TX. In the study, flumazenil, hydroxyzine, and gabapentin, all of which were approved by the US Food and Drug Administration for indications other than drug dependence, were used off-label for the treatment of methamphetamine dependence. Fifty persons who had used methamphetamine within 7 days of study entry were enrolled and received the treatment. Treatment lasted 4 weeks, followed by 8 weeks of weekly follow-up visits to monitor for methamphetamine use via urine drug tests and self-reporting. Participant retention was higher than expected, with 85% of participants completing the program. Significant decrease in methamphetamine use (P<.001) was noted at 84 days after vs 90 days before treatment. If missing data are counted as days of methamphetamine use, a 47% reduction in use was observed for the entire sample (P<.001) and a 65% reduction for the 36 who completed the 8-week evaluation phase (P<.001). Urine test results and self-reported use were positively correlated (Pearson r=0.72, P<.001). The frequency of cravings was reduced on average by 66% (P<.001), with 30 of 31 (97%) of the 36 who completed the study reporting reduction in cravings. Substantial reductions in methamphetamine cravings and use were observed in all phases of treatment, and the retention rate of participants was high. These findings suggest that the efficacy of the medications and of the entire program in treating methamphetamine dependence should be examined in controlled trials.