Randomised, quadruple-blind crossover trial (n=41) comparing single IV ketamine 0.5 mg/kg to midazolam 0.045 mg/kg for treatment of PTSD.
This randomised, quadruple-blind crossover study tested whether a single intravenous infusion of ketamine (0.5 mg/kg over 40 minutes) reduces core PTSD symptoms compared with active comparator midazolam (0.045 mg/kg IV).
Forty-one participants with DSM-IV PTSD (CAPS score ≥50) received two single-dose infusions in a crossover design with clinical and cognitive assessments; memory impairment during infusion was examined as a predictor of clinical response.
Safety monitoring emphasised acute cardiovascular effects and transient intoxication; previous work indicates limited adverse effects other than transient dissociation and increases in blood pressure.
Single IV infusion 0.5 mg/kg over 40 minutes; crossover design.
Infused over 40 minutes
Single IV infusion 0.045 mg/kg over 40 minutes (active comparator).
Midazolam 0.045 mg/kg IV, infused over 40 minutes; recorded as active comparator (compound stored as placebo reference)
This first double-blind (active) placebo-controlled study (n=30) of repeated ketamine (6x, 35mg/70kg) infusions found it to be effective as a treatment for PTSD (67% clinical response), but this response faded (on average) within a month.