One promising approach in treating antibiotic-resistant bacteria is to “break” resistances connected with antibacterial efflux by co-administering efflux pump inhibitors (EPIs) with antibiotics. Here, ten compounds, previously optimized to restore the susceptibility to ciprofloxacin (CIP) ofnorA-overexpressingStaphylococcus aureus, were evaluated for their ability to inhibitnorA-mediated efflux inStaphylococcus pseudintermediusand synergize with CIP, ethidium bromide (EtBr), gentamycin (GEN), and chlorhexidine digluconate (CHX). We focused efforts onS. pseudintermediusas a pathogenic bacterium of concern within veterinary and human medicine. By combining data from checkerboard assays and EtBr efflux inhibition experiments, the hits 2-arylquinoline1, dihydropyridine6,and 2-phenyl-4-carboxy-quinoline8were considered the best EPIs forS. pseudintermedius. Overall, most of the compounds, except for 2-arylquinoline compound2, were able to fully restore the susceptibility ofS. pseudintermediusto CIP and synergize with GEN as well, while the synergistic effect with CHX was less significant and often did not show a dose-dependent effect. These are valuable data for medicinal chemistry optimization of EPIs forS. pseudintermediusand lay the foundation for further studies on successful EPIs to treat staphylococcal infections.