Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a perphenazine stimulus. Perphenazine is a phenothiazine derivative having a chloro substituent at the 2-position and a 3-[4-(2-hydroxyethyl)piperazin-1-yl]propyl group at the N-10 position.