The present invention relates to a biocorrodable implant in which corrosion may be triggered or accelerated after implantation by applying an external stimulus, the implant having a base body which is completely or partially composed of a biocorrodable metallic material, and the base body having a coating with a protective layer which is not biocorrodable. According to the invention, the implant has control elements which are configured in such a way that the protective layer, optionally in combination with the control elements, completely or partially encloses the base body so as to be impermeable to bodily medium, and the protective layer being convertible to a form which is permeable to bodily medium as the result of a change in shape of the control elements which may be regulated and/or controlled by an external stimulus.