The invention relates to an adhesive and binder for dermal or transdermal therapy systems, consisting of (a) a (meth)acrylate copolymer composed of radically polymerized C1 to C4 alkyl esters of acrylic or methacrylic acid and (meth)acrylate monomers with a cationic ammonium group in the alkyl radical, containing (b) 0.1-45 wt.-% with reference to (a) of an organic dicarboxylic or tricarboxylic acid or an acrylate or (meth)acrylate polymer or copolymer containing an acid group, as well as (c) 20-80 wt.-% with reference to (a) of a plasticizer, and (d) if necessary, a pharmaceutically active substance and/or pharmaceutically usual additives, characterized in that dibutyl sebacate is contained as the plasticizer.