Ketamine Is an Effective Adjunct to Morphine for Pain, Even at Low Doses

Although the use of ketamine as an adjunct to opioid treatment for pain has been previously described (NEJM JW Emerg Med Oct 15 2003), it is not widely used for this purpose in the emergency department (ED). Researchers compared morphine plus saline placebo versus morphine plus ketamine at two doses (0.3 mg/kg and 0.15 mg/kg) in a randomized, double-blind trial of 60 adult ED patients who required intravenous opioids for moderate to severe pain.

Patients in each of the ketamine groups achieved significantly greater pain relief over 2 hours (the primary outcome) than those in the placebo group. However, by 2 hours after drug administration, patients in the lower-dose ketamine group had comparable improvement in pain relief to those in the pla…