Purpose: Ketamine is effective on neuropathic pain that is difficult to respond to opioids among cancer pains, due to its N-methyl-D-aspartate (NMDA) receptor antagonism action. The purpose of this study was to evaluate the effect of oral ketamine on neuropathic pain. Methods: We retrospectively investigated the dosage and the administration period of oral ketamine in 31 patients for one year from December 2004. Results: Pain-relief was achieved in 22 of 31 patients, the average of initial dose was 107.3mg/day and the average administration period was 63 days. Seven patients discontinued oral ketamine within 7 days because of nausea/ vomiting (4 patients) or drowsiness (3 patients). Two patients had no sufficient pain-relief. Conclusion: This experience suggests that oral ketamine is effective on the management of neuropathic pain. Palliat Care Res 2008; 3(1): 216-220

Mistake in Japanese Sentence had been corrected