Journal of Affective Disorders
July 15, 2025
Theresa R. Lii, Josephine R. Flohr, Robin L. Okada et al.
1 citation
The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo...
medRxiv : the preprint server for health sciences
November 2, 2024
Theresa R. Lii, Josephine R. Flohr, Robin L. Okada et al.
preprint
The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo...
Nature Mental Health
October 19, 2023
Theresa R. Lii, Ashleigh E. Smith, Josephine R. Flohr et al.
94 citations
Ketamine may have antidepressant properties, but its acute psychoactive effects complicate successful masking in placebo-controlled trials. Here we present a single-center, parallel-arm, triple-masked, randomized, placebo-controlled trial assessing the antidepressant efficacy of intravenous ketamine masked by surgical anesthesia (ClinicalTrials.gov, NCT03861988). Adult patients (N = 40) with...
medRxiv Preprint Server
April 28, 2023
Theresa R. Lii, Ashleigh E. Smith, Josephine R. Flohr et al.
28 citations
preprint
Abstract BACKGROUND Ketamine may have antidepressant properties, but its acute psychoactive effects complicate successful masking in placebo-controlled trials. METHODS In a triple-masked, randomized, placebo-controlled trial, 40 adult patients with major depressive disorder were randomized to a single infusion of ketamine (0.5 mg/kg) or placebo (saline) during anesthesia as usual for routine...