Randomised, triple‑blind, parallel‑group ED study (n=21) comparing a single IV bolus of ketamine 0.25 mg/kg versus diphenhydramine 25 mg for rapid antidepressant effects in patients with severe MDD.
Randomised, triple‑masked, parallel trial testing a single sub‑anesthetic IV ketamine bolus (0.25 mg/kg) versus an equivalent volume of diphenhydramine (25 mg) in Emergency Department patients presenting with severe major depressive disorder.
Primary analyses compare mood measures pre‑ and post‑infusion; secondary measures include heart rate and heart‑rate variability, serum inflammatory cytokines (IL‑1, IL‑2, IL‑6, IL‑8, IL‑10, IL‑12, TNF‑α), BDNF, and serum magnesium to explore biological correlates of response.
Aim is to determine the rapidity and persistence of ketamine's antidepressant effects in ED patients to potentially reduce need for inpatient admission and provide a safety bridge to outpatient care.
Single sub‑anesthetic IV ketamine bolus for rapid antidepressant effect in ED patients with MDD.
IV bolus over 1–2 minutes; single infusion.
Active comparator (diphenhydramine 25 mg IV) used as blinding/control.
Diphenhydramine 25 mg IV (Benadryl) delivered as equivalent volume; encoded as active comparator in notes.