Effects of intravenous antidepressant drugs on the excitability of human motor cortex: a study with paired magnetic stimulation on depressed patients.

Background: The effect of various drugs was investigated by using transcranial magnetic stimulation (TMS) both in healthy subjects and patients, and the results indicated an influence of antidepressant drugs (ADs) on motor excitability.

Objective: The aim of our study was to analyze the effects of two ADs, the tricyclic (TCA) clomipramine and the serotoninergic antidepressant (SSRI) citalopram on the motor cortex excitability in major depressed patients with TMS.

Methods: Thirty affected subjects were placed into three groups: two received an intravenous dose of 25 mg clomipramine or 40 mg citalopram, and one received an injection of a placebo.