Phenazopyridine hydrochloride (PHZ) and Trimethoprim (TMP) are formulated together to treat urinary tract infections. The current work describes the first electrochemical sensor to simultaneously determine PHZ and TMP with good anodic peak potential separation. A rapid, simple and sensitive electrochemical oxidation based on using multiwalled carbon nanotubes (CNT) and sugar polymer (PS) as modifier carbon paste (CNT/PS/MCPE) is described. Under optimized conditions and by using square wave voltammetry, a wide linearity range of 2×10-7 M to 1 ×10-4 M was obtained for both drugs with good recovery in pH 7. The high sensitivity and good reproducibility enabled using the modified electrode to determine PHZ and TMP in pharmaceutical formulation, human serum and urine. The proposed voltammetric method was statistically compared with the reported spectrophotometric method and the results obtained indicate no significant differences. Moreover, the fabricated sensor was applicable for the determination of PHZ and TMP in presence of common interfering molecules, ascorbic acid and uric acid which can be present in the plasma and urine. Analytical Eco-scale was applied to evaluate the greenness of the proposed voltammetric method.