Differential effects of the antidepressant mirtazapine on amphetamine- and dizocilpine-induced PPI deficits

► Mirtazapine reversed the PPI impairment caused by amphetamine. ► Mirtazapine was not effective in reversing the PPI impairment caused by dizocilpine. ► H1, α2 adrenergic, and possibly 5-HT antagonist effects of mirtazapine contribute to its efficacy in reversing PPI deficits caused by amphetamine. ► The muscarinic antagonism of mirtazapine may limit mirtazapine's efficacy.