The effects of a multiday (10-14 days) subanesthetic dose IV ketamine infusion in the treatment of refractory chronic pain.

Ketamine is an anesthetic agent that at lower doses can be a potent analgesic. There has been an interest in the use of low dose ketamine in treatment of chronic pain syndromes. We report the results of a retrospective observational study for patients diagnosed with a chronic noncancer pain syndrome receiving a 2-week continuous subanesthetic IV ketamine infusion. We conclude that a 10-14 days of subanesthetic ketamine infusion in chronic patients results in clinically significant lowering of patients' numerical pain score. Further studies looking at subanesthetic ketamine infusion in a prospective trial of multi-day IV ketamine infusion in chronic refractory chronic neuropathic pain are needed to further assess the efficacy of ketamine.