Drug biomonitoring using developed modified sensors, especially with recent electrochem. techniques, is considered an essential step and plays a significant role in the good detection of several drugs in biofluids, minimizing the damages resulting from their overdoses.This work is based on the detection of three important drugs such as paracetamol (PCM), sulpiride (Sulp), and bromhexine hydrochloride (Brh-HCl) with different pharmaceutical families.A specific sensor was fabricated called the carbon paste electrode (CPE) based on Ca0.7La0.3Fe0.3Ni0.7O3 (CLFN) nanoparticles (NPs) synthesized by a citrate method and modified with black carbon (BC).A low-cost, highly sensitive BC/CLFN NPs/CPE sensor was prepared for the simultaneous determination of the three drugs using cyclic voltammetry (CV), differential pulse voltammetry (DPV), square wave voltammetry (SWV) and electrochem. impedance spectroscopy (EIS).Physicochem. characterization was conducted using X-ray diffraction (XRD) and SEM (SEM).The calculated crystallite size using the Debye-Scherer equation was 237.08 nm by XRD, while the nanoparticles grain size was 60.27 nm extracted from SEM surface images.As a result, the developed sensor demonstrates a high response and sensitivity towards PCM, Sulp, and Brh-HCl mols. compared to literature with excellent and low detection limits of 0.36 μM, 0.042 μM, and 2.88 μM for PCM, 0.073 μM, 0.12 μM, 15.45 μM for Sulp, and 0.407 μM, 0.17 μM, 7.82 μM for Brh-HCl drug by CV, DPV and SWV techniques, resp.High sensitivities of 6588.07, 149.73, and 83.35 μA.μM-1.cm-2 for PCM, Sulp, and Brh by CV technique, resp. with wide linear range from 0.01 μM to 180 μM for PCM, from 0.1 μM to 160 μM for Sulp, and from 0.5 μM to 240 μM for Brh by DPV technique.Addnl., the modified CLFN NPs/BC/CPE sensor demonstrated excellent results in real pharmaceutical samples for all three drugs.The reported results include very good recoveries of 104.21 %, 98.68 %, and 95.50 %, and excellent relative standard deviations of 1.18 %, 1.52 %, and 2.84 %, resp.