This study develops a dual fluorescence probe strategy using glutathione-capped copper nanoclusters (GSH-CuNCs) and nitrogen-doped carbon dots (N-CDs) for the simultaneous analysis of cisplatin (CIS) and etoposide (ETP) in patient plasma. The fluorescence signal of GSH-CuNCs at 615 nm increased linearly with CIS concentration while the N-CD emission at 480 nm remained unaffected. Conversely, the N-CD fluorescence was selectively enhanced by ETP with no interference from CIS. Extensive materials characterization confirmed the synthesis of the nanoprobes. The sensor showed high sensitivity with limits of detection of 6.95 ng mL−1 for CIS and 7.63 ng mL−1 for ETP, along with excellent selectivity against potential interferences in rabbit plasma. The method was applied to real rabbit plasma samples and estimated the pharmacokinetic parameters of CIS before and after coadministration with ETP, revealing minor changes that suggest no significant impact on CIS's pharmacokinetics. This rapid and simple fluorescence strategy offers significant advantages in terms of cost-effectiveness, ease of operation, and high throughput analysis, making it promising for clinical applications requiring frequent drug monitoring.This study develops a dual fluorescence probe strategy using glutathione-capped copper nanoclusters (GSH-CuNCs) and nitrogen-doped carbon dots (N-CDs) for the simultaneous analysis of cisplatin (CIS) and etoposide (ETP) in patient plasma. The fluorescence signal of GSH-CuNCs at 615 nm increased linearly with CIS concentration while the N-CD emission at 480 nm remained unaffected. Conversely, the N-CD fluorescence was selectively enhanced by ETP with no interference from CIS. Extensive materials characterization confirmed the synthesis of the nanoprobes. The sensor showed high sensitivity with limits of detection of 6.95 ng mL−1 for CIS and 7.63 ng mL−1 for ETP, along with excellent selectivity against potential interferences in rabbit plasma. The method was applied to real rabbit plasma samples and estimated the pharmacokinetic parameters of CIS before and after coadministration with ETP, revealing minor changes that suggest no significant impact on CIS's pharmacokinetics. This rapid and simple fluorescence strategy offers significant advantages in terms of cost-effectiveness, ease of operation, and high throughput analysis, making it promising for clinical applications requiring frequent drug monitoring.