Abstract: A vein catheter dressing comprising a supporting foil (1), an adhesive layer (2) on one side of the foil, a liquid-absorbent pad (3) placed centrally on the adhesive layer, the pad being considerably smaller than the supporting foil (1) and being preferably placed within or substantially within one-half of the supporting foil when the foil is divided transversely, and further comprises two release foils (8,9) over the adhesive layer and meeting over or in the vicinity of the pad (3), and a slit (6) which departs from one edge of the dressing and extends substantially up to the pad (3), optionally also through a part of the pad, wherein a window aperture is provided in the supporting foil and optionally also in the adhesive layer (2) in the vicinity of the pad on that side thereof which lies opposite the slit (6), this window aperture being covered with a layer of transparent material (5).