Methamphetamine use is very common in the US and is associated with serious medical and
psychiatric problems. There has also been a significant increase in the number of patients
entering treatment for methamphetamine dependence, however, no pharmacologic treatment has
been identified as effective in treating methamphetamine addiction. Given that withdrawal
from methamphetamine is thought to contribute to relapse to methamphetamine use during early
treatment, it is important to examine potential pharmacologic agents for alleviating
withdrawal. Thus, this study is designed to study methamphetamine withdrawal in humans. To
this end, 30 methamphetamine dependent participants (ages 18-65 years) will be entered into a
4-week residential study. Urine samples will be obtained at baseline to ensure recent
methamphetamine use. Intake assessments will include cognitive testing, standardized
assessment of depression and anxiety, profile of mood states, methamphetamine selective
severity assessment, methamphetamine withdrawal assessment, sleep quality and quantity, a
pre-attentional measure and attentional measure. Upon admission to the residential facility,
all study participants will be started on (20-30mg) long acting amphetamine/d-amphetamine and
stabilized over the first 5 days. After stabilization participants will be randomized based
on sex, amphetamine withdrawal questionnaire score, and methamphetamine selective severity
assessment score to either continued treatment with amphetamine/d-amphetamine or placebo for
2 weeks. All subjects will then be placed on placebo for the last 7 days. The investigators
hypothesis is that stopping amphetamine administration in methamphetamine dependent
individuals will negatively impact mood, sleep and cognitive function in a time-limited
fashion that may differ depending upon the measure and that attentional, but not
pre-attentional, measures will be adversely affected in those receiving placebo compared to
those maintained on amphetamine.