LACK OF RELAPSE WITH TRYPTOPHAN DEPLETION FOLLOWING SUCCESSFUL TREATMENT WITH ECT

Objective: Although the antidepressant mechanism of ECT is unknown, th ere are considerable data to support serotonergic involvement. The eff ects of tryptophan depletion were studied in patients with major depre ssion treated successfully with ECT. Method: Five patients who had bee n successfully treated with ECT for major depression were studied in a randomized, double-blind, crossover design comparing tryptophan deple tion to a placebo procedure. Results: No effect of tryptophan depletio n on mood symptoms was observed despite more than an 85% decrease in t otal serum tryptophan. Conclusions: These data suggest that presynapti c serotonin availability may not be necessary for the acute maintenanc e of an antidepressant response to ECT.