Current Opinion in Supportive and Palliative Care; Jun 2017; vol. 11 (no. 2) pp 88-92
This review found four randomized controlled trials that examined the
benefit of oral, subcutaneous or intravenous ketamine in opioid refractory
cancer pain but none showed clinically relevant benefit in relieving pain or
reducing opioid consumption. These findings contrast the
benefit from ketamine observed in a large number of open-label studies and
(retrospective) case series. The authors relate the opposite outcomes to methodological
issues. They conclude that there is still insufficient evidence
to state with certainty that ketamine is not effective in cancer pain.