Randomized controlled trial of dexamphetamine maintenance for the treatment of methamphetamine dependence

Pharmacotherapies Research Unit, Drug and Alcohol Services South Australia, South Australia, Australia.
Addiction (Impact Factor: 4.74). 10/2009; 105(1):146-54. DOI: 10.1111/j.1360-0443.2009.02717.x
Source: PubMed


To investigate the safety and efficacy of once-daily supervised oral administration of sustained-release dexamphetamine in people dependent on methamphetamine.
Randomized, double-blind, placebo-controlled trial.
Forty-nine methamphetamine-dependent drug users from Drug and Alcohol Services South Australia (DASSA) clinics.
Participants were assigned randomly to receive up to 110 mg/day sustained-release dexamphetamine (n = 23) or placebo (n = 26) for a maximum of 12 weeks, with gradual reduction of the study medication over an additional 4 weeks. Medication was taken daily under pharmacist supervision.
Primary outcome measures included treatment retention, measures of methamphetamine consumption (self-report and hair analysis), degree of methamphetamine dependence and severity of methamphetamine withdrawal. Hair samples were analysed for methamphetamine using liquid chromatography-mass spectrometry.
Treatment retention was significantly different between groups, with those who received dexamphetamine remaining in treatment for an average of 86.3 days compared with 48.6 days for those receiving placebo (P = 0.014). There were significant reductions in self-reported methamphetamine use between baseline and follow-up within each group (P < 0.0001), with a trend to a greater reduction among the dexamphetamine group (P = 0.086). Based on hair analysis, there was a significant decrease in methamphetamine concentration for both groups (P < 0.0001). At follow-up, degree of methamphetamine dependence was significantly lower in the dexamphetamine group (P = 0.042). Dexamphetamine maintenance was not associated with serious adverse events.
The results of this preliminary study have demonstrated that a maintenance pharmacotherapy programme of daily sustained-release amphetamine dispensing under pharmacist supervision is both feasible and safe. The increased retention in the dexamphetamine group, together with the general decreases in methamphetamine use, degree of dependence and withdrawal symptom severity, provide preliminary evidence that this may be an efficacious treatment option for methamphetamine dependence.

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Available from: Matthew Smout, Jul 04, 2014
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    • "The general class of abused stimulants also includes drugs such as amphetamine , methamphetamine, and emerging cathinone analogs that function as substrates at dopamine transporters to promote dopamine release (Baumann et al, 2012a; Cameron et al, 2013; Rothman et al, 2001). Recent clinical trials and a human laboratory study found that amphetamine maintenance failed to produce significant decreases in methamphetamine consumption (Galloway et al, 2011; Longo et al, 2010; Pike et al, 2014). These and related results have been interpreted to suggest that dopamine releasers such as amphetamine may be more effective to treat abuse of dopamine uptake inhibitors (eg, cocaine) than abuse of other dopamine releasers. "
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    • "August 2012 | Volume 3 | Article 77 | 1 Longo et al. (2010) reported d-amphetamine produced enhanced retention and decreased illicit use in a methamphetamine abusing population. These reports, along with multiple community clinic and case series reports of reductions in amphetamine abuse during d-amphetamine maintenance, point to potential utility. "
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