Transdermal or topical plasters containing active ingredient are provided that include a non-occlusive back layer, a matrix formed from of one or more polymer layers having at least one pharmaceutical active ingredient in one or more of the layers, in which the structure-forming base polymers of the layer(s) are non-occlusive or only slightly occlusive and a second polymer that has a low water-vapor permeability and that is immiscible or only very slightly miscible with the base polymer is dispersed in at least one of the polymer layers.