The invention relates to a textile fabric for placing on the skin and/or a wound of a patient, having a top side facing away from the skin and an underside facing the skin, the textile fabric having a moisture-impermeable barrier 14 on said underside, wherein the textile fabric is formed from non-conductive warp threads and non-conductive weft threads and from conductive warp threads and conductive weft threads, which are arranged such that an electrically conductive structure 5 consisting of conductive warp and/or weft threads K, S is formed in the textile fabric. Furthermore, the invention relates to a transdermal patch for applying an active substance contained in an active substance reservoir 17 to the skin of the patient, having such a textile fabric, and to an arrangement of a transdermal patch and an evaluation unit 20 for sensing the quantity of active substance contained in the active substance reservoir of the transdermal patch. The preferred embodiment of the invention provides for the sensing of measured values by means of a first and second sensor 6, 7 which are formed by conductive warp and/or weft threads K, S. The first sensor 6 is arranged in the region of a first cutout 18 and the second sensor 7 is arranged in the region of a second cutout 19 in the moisture-impermeable barrier 14. One of the two sensors 6, 7 is a moisture sensor which allows the measurement of moisture, in particular sweat, on the skin of the patient, while the other sensor 7, 6 can be used to sense any desired state or any desired variable. The measurement of the moisture allows the compensation of the influence of sweat on the skin of the patient on the sensing of the state or of the variable, for example the quantity of an active substance in a transdermal patch.