In this communication, an innovative dual band microstrip patch antenna is proposed for Implantable Medical Devices (IMD). Particularly, the covered bands are MICS (402- 405MHz) and ISM (2.4-2.48GHz). The antenna has a multilayer configuration where the feeding line and radiating layer are located at different levels. The radiating element of the antenna is a Split Ring Resonator (SRR) coupled to a Spiral. Both elements are short-circuited to the ground plane to achieve size reduction. In addition, the effects of human body geometry and dielectric properties are studied. Three models are investigated: single-layer, three-layer and a realistic human body based on the Voxel Man dataset.