Chlorpromazine potentiates levofloxacin and ciprofloxacin activity against Klebsiella pneumoniae isolates

Gun M. A., YILDIRIM K., Atas C., Uzuner F., ÇOBAN A. Y.

Future Microbiology, cilt.21, sa.4, ss.373-380, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 21 Sayı: 4
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1080/17460913.2026.2654379
  • Dergi Adı: Future Microbiology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, EMBASE, MEDLINE
  • Sayfa Sayıları: ss.373-380
  • Anahtar Kelimeler: antimicrobial resistance, Chlorpromazine, efflux pump inhibition, Klebsiella pneumoniae, quinolone resistance
  • Akdeniz Üniversitesi Adresli: Evet

Özet

Aims: This study aimed to evaluate the in vitro effect of chlorpromazine (CPZ), a phenothiazine antipsychotic, on the susceptibility of Klebsiella pneumoniae to quinolone antibiotics. Materials and methods: Standard microdilution assays were performed to determine minimum inhibitory concentrations (MICs) of levofloxacin (LEV) and ciprofloxacin (CIP), alone and in combination with CPZ, against clinical isolates of K. pneumoniae. MIC values were compared between quinolone-susceptible and quinolone-resistant isolates. Results: Co-administration of CPZ has resulted in significant reductions in MIC values of both quinolones, with a more pronounced effect observed in quinolone-susceptible isolates. More limited MIC reductions have also been observed in quinolone-resistant isolates. Conclusions: Chlorpromazine enhances quinolone activity against K. pneumoniae in vitro, particularly in quinolone-susceptible isolates. Although the observed effects are more limited in resistant strains, the findings indicate that CPZ may serve as a potential adjuvant to improve quinolone activity. Further studies are required to evaluate the clinical relevance of this approach.