The present invention relates to an adhesive wafer suitable for attachment to the skin or a wound, the wafer comprising a dressing sheet comprising a layer of skin-friendly adhesive, the adhesive layer being provided with a backing layer on the non-skin-facing surface thereof, and a flexible protection layer on the skin-facing surface of the adhesive layer, the protection layer protecting the adhesive layer before use of the wafer and the protection layer being attached to the adhesive layer in such a way that it is releasable and wherein the protection layer is in the form of a porous material.