Author: Louise Gagnon
A single infusion of ketamine lessened pain and post traumatic stress disorder (PTSD) symptoms in veterans, without persisting dissociative symptoms or side effects, according to a study presented at the Virtual 2021 Annual Meeting of the Anxiety and Depression Association of American (ADAA).
Sonalee Joshi, University of Michigan, Ann Arbor, Michigan, and colleagues compared the impact of either ketamine (0.5 mg/kg) or ketorolac (15 mg) reconstituted in 500 cc of saline over a 40-minute intravenous infusion in 40 patients with chronic pain, with or without PTSD.
Participants completed the Impact of Events Scale-Revised, evaluating PTSD symptoms at study entry, 24 hours after infusion, and 1-week post-infusion. They also completed the Visual Analogue Scale for pain and the Clinician-Administered Dissociative States Scale (CADSS) for dissociative symptoms at study entry and at 15, 25, and 40 minutes after infusion. CADSS was also measured at 1, 2, and 7 days after infusion.
Among the 20 patients with chronic pain only, ketamine administration was linked to greater dissociative symptoms during the infusion compared with ketorolac administration (P< .001). Among the 20 patients with chronic pain and PTSD, there was no difference in medication efficacy (P> 0.1).
“The patients with PTSD saw symptoms alleviated 1 week post-infusion, regardless of medication they received,” said Joshi. “Within the chronic pain alone group, ketamine had a greater impact on reducing pain symptoms than ketorolac over time.”
It was notable that patients in the chronic pain alone group saw greater dissociative symptoms over the course of the infusion for both ketamine and ketorolac administration, but patients with pain and PTSD did not show this impact.
“Our results suggest that both ketamine and ketorolac may contribute to relief of PTSD symptoms and pain symptoms over the course of 7 days,” said Joshi. “This study is among the first to examine the effects of ketamine on veterans with both chronic pain and PTSD symptoms. These findings show promise for the use of low-dose ketamine as a potential treatment in the future.”