Lithium attracted much attention as a potential neuroregenerative therapy based on experiments in animal models of SCI in 2004. However, toxic levels of lithium (>1.5 mmol/L) are close to the effective levels (0.6 - 1.2 mmol/L). At toxic levels, patients may become confused and lethargic, have diarrhea, upset stomach, and develop tremors, ataxia, dysarthria, and nystagmus. Lithium toxicity may be compounded by sodium depletion or diuretics (thiazides) that inhibit kidney sodium upgrade and ACE inhibitors. Plasma levels also depend on fluid input/output. Therefore, care will be taken to titrate the dose and to test plasma levels of the drug at the beginning, at day 2, 7, and week 6 during the treatment period.