The trend of microelectronic products in the biomedical field is toward higher functionality and miniaturization. As with other electronic devices, the miniaturization of biomedical devices is limited by the reliability of the manufactured product at a desired circuit density. Biomedical device failure or the disorder of biomedical device function during diagnosis and treatment processes may have extremely negative effects. Thus, in order to determine the ultimate performance, the reliability must be modeled for specific operating condition. In this section, hot-carrier-induced degradation of an electroencephalogram (EEG) band-pass filter structure composed of symmetrical CMOS OTAs is investigated. In this context, we propose a degraded transistor-based circuit degradation simulation method that is applicable to any CMOS device. The proposed method is based on the determination of the degraded transistors in the structure under stress conditions and includes the use of a degraded transistor model to adapt the experimental results of the transistor degradation to the simulation. In our study, we first simulated the symmetrical CMOS OTA degradation, considering the output current. Furthermore, to demonstrate the accuracy of the proposed method, the changes in the cutoff frequencies of the first- and second-order low-pass filters, composed of symmetrical CMOS OTAs, were investigated.