A new role of metformin as an efflux pump inhibitor in klebsiella pneumonia

This finding was further confirmed genotypically by polymerase chain reaction that showed the presence of efflux genes AcrA, AcrB, TolC and mdtk in these isolates. The ability of metformin to inhibit efflux activity was compared with the reference efflux pump inhibitors verapamil and ascorbic acid. Metformin was more active than ascorbic acid and less active than verapamil. Up to our knowledge, this is the first report that shows that metformin has an efflux pump-inhibiting activity in Klebsiella pneumoniae.