The present study introduces a novel eletriptan hydrobromide (ELE) sensor based on carbonaceous nanostructures for sensitive voltametric determination of ELE in various pharmaceutical and biological samples. Comprehensive and deep optimization studies were carried out concerning the electrode matrix composition, modification mode, the effect of pH, and other electroanalytical parameters. Surface functionalization of the electrode surface with multiwall carbon nanotubes (MWCNTs) exhibited the highest electrochemical performance with a sharp oxidation peak at about 0.75 V in BR buffer pH 3. Based on the theoretical molecular orbital calculation studies on the ELE molecule and electroanalytical findings, the electrooxidation of ELE undergoes through oxidation of the amine nitrogen atom (N 2) with the transfer of one electron/proton in the electrode reaction. High sensitivity with linear calibration curve were reported within the ELE concentration range from 0.027 to 1.1 µg mL−1 with limit of detection 0.008 µg mL-1. The recorded sensitivity of the proposed sensors encouraged their applications for monitoring of ELE residues in pharmaceutical formulation and biological samples.