Which antibiotic allows for once-daily dosing due to its long postantibiotic effect?

Gentamicin is an aminoglycoside antibiotic that is known for its long post-antibiotic effect (PAE). The PAE refers to the continued suppression of bacterial growth after the antibiotic concentration has fallen below the minimum inhibitory concentration (MIC). This characteristic allows for less frequent dosing, such as once daily, which is beneficial in managing patient compliance and minimizing side effects associated with gentamicin.

The dosing regimen is clinically advantageous because it permits higher peak plasma concentrations while maintaining lower trough levels. This not only enhances the efficacy of the drug but also helps to reduce the risk of toxicity, particularly nephrotoxicity, which is a concern with aminoglycosides.

While penicillin G, vancomycin, and aztreonam have their own dosing strategies, they do not exhibit the same long post-antibiotic effect that gentamicin does, making it unsuitable for once-daily dosing in many cases. This highlights the unique pharmacokinetic profile of gentamicin in the context of antibiotic therapy.