Lumanauw DD, et al. - Via performing a randomized double-blind placebo-controlled trial including 106 subjects, researchers investigated the efficacy of subdissociative-dose ketamine (SDDK) in reducing acute exacerbations of chronic pain. Thirty five patients received 0.5 mg/kg ketamine, 36 received 0.25 mg/kg ketamine, and 35 received placebo after randomization. Acute exacerbations of chronic pain were effectively treated with ketamine infusions at both 0.5 and 0.25 mg/kg over 20 minutes but with more adverse effects compared to placebo. No longer-term pain control over the next 24 to 48 hours was reported with ketamine.