Multi-target and continuous monitoring by wireless implantable devices is of increasing interest for personalized therapy. In this work an implantable system is presented which is capable of measuring different drugs with Cyclic Voltammetry (CV) method. The wireless microsystem consists of four modules, namely (i) The inductive coil; (ii) Power management IC; (iii) Readout and control IC; (iv) Biosensor array. The power management IC provides 1.8 V with as high as 2 mW power for the readout IC. The configurable readout IC is able to control the biosensor array and measure the sensor current in CV method. CV experiments performed with this microsystem well agree with a commercial equipment for two well known anti-cancer drugs, Etoposide and Mitoxantrone, detection.