Antibiotic Treatment of Common Infections

More Evidence to Support Shorter Durations

Benjamin J. Smith; George Heriot; Kirsty Buising


Curr Opin Infect Dis. 2020;33(6):433-440. 

In This Article

Abstract and Introduction


Purpose of Review: Although there is increasing recognition of the link between antibiotic overuse and antimicrobial resistance, clinician prescribing is often unnecessarily long and motivated by fear of clinical relapse. High-quality evidence supporting shorter treatment durations is needed to give clinicians confidence to change prescribing habits. Here we summarize recent randomized controlled trials investigating antibiotic short courses for common infections in adult patients.

Recent Findings: Randomized trials in the last five years have demonstrated noninferiority of short-course therapy for a range of conditions including community acquired pneumonia, intraabdominal sepsis, gram-negative bacteraemia and vertebral osteomyelitis.

Summary: Treatment durations for many common infections have been based on expert opinion rather than randomized trials. There is now evidence to support shorter courses of antibiotic therapy for many conditions.


Antibiotic overuse is now a well-recognized problem associated with the development of antimicrobial resistance and adverse patient outcomes including Clostridioides difficile infection. Although there are select examples where stopping antibiotic therapy when symptoms have improved may result in adverse outcomes (such as tuberculosis or Staphlycoccus aureus bacteraemia) this is not the case for many common infections. Indeed, there is increasing evidence that many infections can be treated safely and effectively with courses significantly shorter than traditionally recommended.

Unfortunately, standard treatment durations for many infections may be based on convention rather than robust evidence and physician surveys suggest that prescribing is more often motivated by fear of undertreating than by concerns of adverse effects of the antibiotics themselves.[1] High-quality evidence supporting the safety of shorter treatment durations is needed to give clinicians confidence to change practice.

Observational studies comparing antibiotic durations are likely to be confounded by unmeasured differences between patient groups that have impacted the decision to give short or prolonged treatment. Therefore, inferences about optimal treatment durations should ideally be drawn from randomized controlled trials (RCTs). Here we present the results of a systematic review of RCTs comparing short and long antibiotic treatment durations in adult patients for common infections over the past five years (Table 1). Each of these trials will be discussed in the context of the traditional clinical practice and/or current guideline recommendations.