This is a randomized, placebo-controlled, double-blinded trial. Forty patients will be randomized into two groups. The subjects in the Treatment Group will be administered with lithium carbonate, while the Control Group will receive placebo.

Each subject will receive oral lithium carbonate or placebo for six weeks. In the treatment group, the dose will be adjusted according to the serum lithium level while in the control group there will be a sham adjustment.

The outcomes will be assessed 6 weeks and 6 months after the onset of the medication. The outcomes will be compared with baseline pre-treatment data to obtain "neurological change scores." The efficacy and safety will be analyzed comparing the results of the treatment group with those of the control group.

Inclusion Criteria:

• Subjects of either gender and 18-60 years of age;
• Subjects with chromic spinal cord injury (defined as a history of spinal cord injury for 12 months or longer);
• Subjects with ASIA - classification of A, B, or C for at least 6 months unchanged;
• Spinal cord injury vertebral level should be between C4 and T10;
• Subjects must be able to read, understand, and complete the VAS;
• Subjects who have voluntarily signed and dated an informed consent form, approved by an IRB/IEC, prior to any study specific procedures.

Exclusion Criteria:

• A history of hypersensitivity or other adverse reaction to lithium;
• Significant renal, cardiovascular, hepatic and psychiatric disease;
• Significant medical diseases or infection;
• Addison's disease;
• Debilitation or dehydration;
• Recently taken or are taking diuretics or other drugs with known interaction with lithium, such as tricyclic antidepressants, NSAIDs and tetracyclines;
• A history of alcohol abuse or drug abuse;
• Pregnant or lactating women;
• Female of childbearing potential and are unwilling to use an effective contraceptive method while enrolled in the study;
• Subjects who are currently participating in another investigational study or has been taking any investigational drug within the last 4 weeks prior to screening of this study;
• Subjects who have taken lithium for manic depression or other psychiatric conditions,and finally;
• Any criteria, which, in the opinion of the investigator, suggests that the subject would not be compliant with the study protocol.

6 months