The feature of neuropathic pain may occur in the absence of any apparent stimulus and be exaggerated in either amplitude or duration. Peripheral nerve injury may produce neuropathic pain and opioids have been shown to be relatively unsatisfactory for the treatment of most cases of neuropathic pain. The NMDA receptor system is involved in transmission and modulation of nociceptive information. We treated patients with severe pain, hyperaesthesia and allodynia with epidural injection of NMDA receptor antagonist, ketamine (10 mg) and morphine (0.5 mg) or other opioid. The combinations provided effective pain management in 23 patients with neuropathic pain.