This is a prospective, randomized, double-blind, placebo-controlled study, in which we will systematically evaluate the therapeutic effects of citicoline, which may both increase dopamine and normalize cognitive and structural deficits in the brains of methamphetamine dependent subjects. Methamphetamine dependent subjects will undergo baseline and repeat cognitive assessments after 8-9 weeks of placebo or oral citicoline as a nutritional supplement. We will also evaluate the chemical and structural changes in brain regions identified by magnetic resonance spectroscopy (MRS), diffusion tension imaging (DTI) and cortical thickness, which in turn are expected to recover after 8-9 weeks of citicoline treatment. Specific brain regions of interest include the prefrontal cortices, temporal cortex, and the caudate/putamen all of which are known to be involved in the pathophysiology of methamphetamine dependence.