Amplitudes of somatosensory evoked potentials reflect cortical hyperexcitability in antidepressant-induced myoclonus.

During treatment with therapeutic dosages of cyclic antidepressants, 2 patients experienced reversible myoclonus. These episodes were accompanied by enlarged cortical somatosensory evoked potentials (SEP). We suggest that SEP amplitudes reflect modifications of cortical excitability during antidepressant treatment.