John Lewis

Publications (3)12.94 Total impact

• Article: A double-blind, placebo-controlled trial of modafinil (200 mg/day) for methamphetamine dependence.

  James Shearer, Shane Darke, Craig Rodgers, Tim Slade, Ingrid van Beek, John Lewis, Donna Brady, Rebecca McKetin, Richard P Mattick, Alex Wodak
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  ABSTRACT: To examine the safety and efficacy of modafinil (200 mg/day) compared to placebo in the treatment of methamphetamine dependence and to examine predictors of post-treatment outcome. Eighty methamphetamine-dependent subjects in Sydney, Australia were allocated randomly to modafinil (200 mg/day) (n = 38) or placebo (n = 42) under double-blind conditions for 10 weeks with a further 12 weeks post-treatment follow-up. Comprehensive drug use data (urine specimens and self-report) and other health and psychosocial data were collected weekly during treatment and research interviews at baseline, week 10 and week 22. Treatment retention and medication adherence were equivalent between groups. There were no differences in methamphetamine abstinence, craving or severity of dependence. Medication-compliant subjects tended to provide more methamphetamine-negative urine samples over the 10-week treatment period (P = 0.07). Outcomes were better for methamphetamine-dependent subjects with no other substance dependence and those who accessed counselling. There were statistically significant reductions in systolic blood pressure (P = 0.03) and weight gain (P = 0.05) in modafinil-compliant subjects compared to placebo. There were no medication-related serious adverse events. Adverse events were generally mild and consistent with known pharmacological effects. Modafinil demonstrated promise in reducing methamphetamine use in selected methamphetamine-dependent patients. The study findings support definitive trials of modafinil in larger multi-site trials.
  Addiction 03/2009; 104(2):224-33. · 4.31 Impact Factor
• Source

  Available from: Alex Wodak

  Article: Pilot randomized double blind placebo-controlled study of dexamphetamine for cocaine dependence.

  James Shearer, Alex Wodak, Ingrid van Beek, Richard P Mattick, John Lewis
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  ABSTRACT: To establish the feasibility of conducting a placebo-controlled clinical trial of dexamphetamine replacement therapy for cocaine dependence and to obtain preliminary data. Double-blind randomized placebo-controlled trial. Thirty cocaine-dependent injecting drug users. Subjects were assigned randomly to receive 60 mg/day dexamphetamine (n = 16) or placebo (n = 14) for 14 weeks. Immunoassay and mass spectrometric techniques were used to identify cocaine metabolites in urine. Subjects were screened using the Composite International Diagnostic Interview and DSM-IV. The Opiate Treatment Index, Brief Symptom Inventory, Severity of Dependence Scale and visual analogue craving scales were used to collect pre- and post-self-report data. Treatment retention was equivalent between groups; however, outcomes favoured the treatment group with no improvements observed in the placebo control group. The proportion of cocaine-positive urine samples detected in the treatment group declined from 94% to 56% compared to no change in the placebo group (79% positive). While the improvements were not significant between groups, within-group analysis revealed that the treatment group reduced self-reported cocaine use (P = 0.02), reduced criminal activity (P = 0.04), reduced cravings (P < 0.01) and reduced severity of cocaine dependence (P < 0.01) with no within-group improvements found in the placebo group. A definitive evaluation of the utility of dexamphetamine in the management of cocaine dependence is feasible and warranted.
  Addiction 08/2003; 98(8):1137-41. · 4.31 Impact Factor
• Article: Pilot randomized controlled study of dexamphetamine substitution for amphetamine dependence

  James Shearer, Alex Wodak, Richard P. Mattick, Ingrid Van Beek, John Lewis, Wayne Hall, Kate Dolan
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  ABSTRACT: Aims. To test the feasibility of conducting a definitive randomized controlled trial of dexamphetamine substitution for amphetamine dependent people and provide preliminary data. Design. An open, two-group pre-post randomized controlled trial. Participants. Forty-one long-term, dependent amphetamine users seeking treatment. Intervention. Twenty subjects were offered weekly counselling. Twenty-one subjects were, in addition, prescribed up to 60 mg dexamphetamine daily. Measurements. Immunoassay and mass spectrometric urinalysis techniques were used to identify the presence of amphetamine and methylamphetamine in urine. The Opiate Treatment Index and Severity of Dependence Scale were used to collect pre- and post-self-report data. Subjects were screened using the Composite International Diagnostic Interview. Findings. Reduced street amphetamine use and amphetamine dependence was observed both in subjects prescribed dexamphetamine and subjects receiving counselling only. Treatment subjects appeared more likely to attend counselling. Conclusions. A definitive randomized controlled trial of dexamphetamine substitution using the techniques and instruments piloted in this study is feasible. Users appeared to be attracted and retained in substitution treatment. The intervention also appeared to be acceptable to clinicians.
  Addiction 08/2001; 96(9):1289 - 1296. · 4.31 Impact Factor