Prolonged vs Intermittent Antibiotic Infusions


  • Recent efforts to maximize antibiotic activity have focused on using pharmacokinetic (PK) and pharmacodynamic (PD) principles for drug administration.

  • As a preferred choice, beta lactams, and specifically meropenem displays a time dependent bactericidal activity based on free concentrations above the minimum inhibitory concentration (MIC).

  • Although additional well controlled studies are needed, it appears prolonged continuous infusions of meropenem provide more favorable outcomes than intermittent infusions.


  • Effective antibiotic treatment is a crucial aspect of sepsis care.
  • Beta lactams are the most prescribed class of agent in the U.S. with meropenem being a common choice for treatment in ICU patients.

  • The best predictor of antibacterial efficacy is the percentage of the dosing interval with free drug concentrations above the MIC. Beta lactams display this type of time-dependent bactericidal activity and PK/PD characteristics.

  • Continuous infusion of beta lactams consistently attain the desired drug exposure. However, there is ongoing debate regarding traditional intermittent dosing regimens versus a continuous infusion regimen.

  • Few well controlled studies exist in the evaluation of continuous vs intermittent administration of meropenem on sepsis outcomes.


  • Overall analysis shows that continuous infusion of meropenem is associated with a lower mortality rate than intermittent intravenous infusions.

  • Risk of death was 24-34% lower with continuous infusion vs intermittent.

  • Clinical success rates were significantly higher in patients receiving prolonged meropenem infusion compared to intermittent infusion.


  • Evidence from mainly non-randomized studies suggest prolonged/continuous infusion of meropenem could produce superior outcomes in patients with sepsis.

  • Prolonged/continuous infusions offers potential benefits by providing antibiotic concentrations above the MIC.

  • Further research of controlled trials with a larger diverse patient populations are warranted.

To receive articles like these in your Inbox, you can subscribe to Sepsis Program Optimization Insights.

Subscribe to sepsis program optimization insights

Erkan Hassan is the Co-Founder & Chief Clinical Officer of Sepsis Program Optimization where he designs & oversees the implementation of solutions to optimize sepsis programs.

To discuss your organization’s Barriers of Effective Sepsis Care, contact Erkan by phone (844) 4SEPSIS (844-473-7747), email (, or video chat.