One of the advantages of infrared neuromodulation (INM) compared to the classical electrical stimulation is that INM does not induce photoelectric artefacts in electrophysiological recordings. Another advantageous property of INM is that the propagation of light can be shaped easier than in case of electrical signals. Therefore, the stimulus can be more directional, the neuromodulation impact can be localized. In this work an infrared optrode is presented, that can be implanted into the brain tissue and performs optical stimulation and multi-site electrophysiological recording simultaneously. This silicon-based microimplant has two modalities integrated into a single needle: extracellular electrophysiological sensing and infrared waveguiding. The optrode’s half-centimetre-long shaft (0.19×0.17 mm) holds 16 platinum recording sites (900 µm2) with 100 µm inter-site distance. Infrared waveguiding property is embedded into the silicon substrate material of the same shaft that ends in a parabolic micromirror. This tip shape aims to direct the outcoupled infrared light laterally towards neighbouring tissue, therefore more photons get absorbed closer to the recording sites causing the positioning of the maximum heating effect in the vicinity of recording sites. The proposed work shows the outcomes of numerous different characterisation methods to demonstrate the in vivo applicability of this optrode. Various optical investigations and thermal tests were made to calibrate the optically induced heating preceding the in vivo use. The first in vivo tests were made in the somatosensory cortex of anaesthetised rats. Our findings owing to the infrared illumination in the recorded extracellular electrophysiological data are presented from various aspects.