Briefly, METH exposure increases Clk1 expression, which subsequently decreases the iron exporter (FPN1) expression, causing an increase in cytoplasm iron content, and also increases lysosomal DAT degradation, causing a reduction in membrane DAT expression. Increased iron content may also facilitate DAT internalization. Accordingly, genetic deletion or pharmacological inhibition of mitochondria Clk1 causes a reduction in cytoplasm iron content and an increase in membrane DAT expression. Increased membrane DAT facilitates DA reuptake from extracellular space and decreases DA response to METH, producing a reduction in METH reward. Similarly, a pharmacological agent that removes excess cytoplasm iron (such as an iron chelator or FPN1 activator) or inhibits DAT internalization would be also effective in attenuation of METH reward and dependence.