An implantable tissue-stimulating device, such as a cochlear implant, having a resiliently flexible elongate member (11) having a plurality of electrodes (12) positioned thereon. The elongate member (11) provides a means of delivering at least one bio-active substance to the implantee following implantation of the elongate member (11). The delivery means can comprise a lumen 21 containing the bio-active substance in a liquid form. The bio-active substance can comprise a steroid or can perform a function of reducing the resting neuron potential of neurons within the cochlea.
