Transdermal therapeutic system with which at least one pharmaceutical active substance that is non-volatile at room temperature can be administered at a daily dose of at most 30 mg, comprising a rear surface directed away from the skin and impermeable to the active substance, an adjoining polymer layer located away from the skin and based on polyisobutylene with a coating weight of at least 80 g/m<2>, an adhesive skin contact layer resting on the skin-remote polymer layer and based on acrylate copolymers with a coating weight of at most 50 g/m<2>, and a protective layer that is impermeable to the active substance and can be peeled off from the skin contact layer.