Complex Regional Pain Syndrome (CRPS), also known as Causalgia and Reflex Sympathetic Dystrophy Syndrome (RSDS); is a peripheral chronic pain syndrome that usually involves an extremity.  This syndrome is associated with increased sensitivity to pain and touch in that extremity, temperature changes, and guarding of the extremity.  Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is most widely known for its use as an anesthetic agent.  The basis for using Ketamine to treat CRPS/RSDS resides in its strong ability to block the NMDA receptors.  Low dose Ketamine IV infusion maintains a level of Ketamine in the central nervous system long enough to reverse the effects of the sensitization process and associated pain.  Ketamine IV infusion has also been shown to be helpful with severe depression where anti-depressant medications are ineffective.  Use of Ketamine for CRPS/RSDS and depression is not FDA approved and not covered by usual insurance.  A substantial number of clinical trials and case studies show that CRPS patients experience greatly reduced pain scores after treatment with Ketamine.  Our practice makes low dose Ketamine available for Sympathetic Syndromes and Severe Depression.  The patient is monitored and given sedation during the process in a certified outpatient surgery center.