Epinephrine levels decrease in responders after electroconvulsive therapy.

We examined potential changes in catecholamine plasma levels and cortisol serum levels in 29 patients with treatment-resistant Major Depressive Disorder (MDD) during a course of electroconvulsive therapy (ECT). Blood samples were taken at three different time points: directly before (T1) and 15 min after (T2) the first ECT, and directly before the last one (T3). Patients responding to ECT had a significant decrease of the intraindividual epinephrine plasma level when both first time points (Δ T1-T2) were compared (χ2 (1) = 10.05, p = 0.002). This finding encourages further investigation in the understanding of the catecholamine-metabolism including its release and uptake in patients with treatment-resistant MDD receiving ECT.