This 4-year study will investigate the effectiveness of methylphenidate for initiating and sustaining abstinence in methamphetamine dependent individuals. Approximately 90 participants seeking treatment for methamphetamine dependence will be enrolled in the study for an initial 2 weeks to establish clinic compliance. During this compliance phase, participants will receive incentives for clinic attendance. After meeting clinic attendance requirements, participants will be randomized to placebo (n = 45) or active study medication (n = 45) conditions, and given 18mg/daily of study drug or placebo for one week, followed by 36mg/daily study drug/placebo for a second week. Finally, participants will be stabilized on 54mg/daily study drug/placebo for the remainder of the study. Placebo participants will be given placebo medications prepared to appear identical to the active medication. In addition, after randomization, all participants will receive motivational incentives for methamphetamine-negative urine tests and begin weekly cognitive behavioral therapy (CBT) provided for the duration of the study.

Inclusion Criteria:

1. Be seeking treatment for their MA use disorder;
2. Be between 18-55 years of age;
3. Meet DSM-IV-TR criteria for MA dependence as assessed by the Mini International Neuropsychological Interview (MINI);

Exclusion Criteria:

1. Have any history or evidence suggestive of seizures or brain injury;
2. Have any known hypersensitivity or previous medically adverse reaction to methylphenidate;
3. Have a neurological or psychiatric disorder, such as psychosis, bipolar illness, motor tics, Tourette's syndrome, or major depression; organic brain disease or dementia; marked anxiety, tension and agitation; or any psychiatric disorder that would require ongoing treatment or that would make study compliance difficult;
4. Have evidence of clinically significant heart disease or hypertension as determined by medical history or physical examination, including pre-existing heart failure, recent myocardial infarction, ventricular arrhythmia, cardiomyopathy, serious heart rhythm abnormalities, and coronary artery disease.
5. Have a family history in first-degree relatives of early cardiovascular morbidity or mortality, as determined by medical history;
6. Have evidence of an untreated or unstable medical illness including: neuroendocrine, autoimmune, renal, hepatic, or active infectious disease (other than HIV);
7. Have clinically significant abnormal vital signs;
8. Have clinically significant abnormal hematology or chemistry laboratory tests [e.g. liver function tests (total bilirubin, ALT, AST, and alkaline phosphatase), kidney function tests (creatinine and BUN)];
9. Have a baseline ECG that demonstrates clinically significant abnormalities;
10. Have known preexisting severe gastrointestinal narrowing,
11. Be pregnant or nursing. Females must either be unable to conceive (i.e., surgically sterilized, sterile, or post-menopausal) or use a reliable form of contraception including hormonal (oral, Depo-Provera or Nuva-ring), intra-uterine devise, sterilization or double barrier method (simultaneous use of two barrier methods such as condom, diaphragm, spermicide);
12. A history of glaucoma;
13. Use of some medications such as Clonidine, coumarin anticoagulants, anticonvulsants (Phenobarbital, phenytoin, primidone), vasopressor agents, and some antidepressants (tricyclics and selective serotonin reuptake inhibitors),. Also, current use of an MAO inhibitor, or use within 14 days of enrollment;
14. Have any other medical condition that would, in the opinion of the study physician, make participation difficult or unsafe.