Effects of electrode placement on the efficacy of titrated, low-dose ECT.

This double-blind, random-assignment study contrasted the relative efficacy of bilateral and unilateral right ECT with a low-dose titration procedure. In 52 patients with primary major depressive disorder, bilateral ECT was markedly superior in short-term symptom reduction to unilateral right ECT. The two conditions did not differ in the duration of generalized seizures or in the number of treatments administered to achieve clinical response. The findings challenge the claim that the elicitation of generalized seizure is, in and of itself, sufficient for the antidepressant properties of ECT. Rather, a dose in excess of seizure threshold may contribute to the efficacy of ECT, particularly with a unilateral right electrode placement.