Antibiotics for community acquired pneumonia in adult outpatients

  • Review
  • Intervention




Community-acquired pneumonia (CAP) is a common condition representing a significant disease burden for the community, particularly for the elderly. Because antibiotics are helpful in treating CAP, they are the standard treatment and CAP thus contributes significantly to antibiotic use, which is associated with the development of bacterial resistance and side-effects. Although several studies have been published concerning CAP and its treatment, the available data arises mainly from studies conducted in hospitalized patients and outpatients. There is no concise summary of the available evidence that can help clinicians in choosing the most appropriate antibiotic.


To summarize the evidence currently available from randomized controlled trials (RCTs) concerning the efficacy of alternative antibiotic treatments for CAP in ambulatory patients above 12 years of age.

Search strategy

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2003, issue 2) which contains the Cochrane Acute Respiratory Infections Groups Specialized Register; MEDLINE (January 1966 to September week 3, 2003), and EMBASE (January 1974 to March 2003).

Selection criteria

We included all randomized controlled trials (RCTs) in which one or more antibiotics were tested for the treatment of CAP in ambulatory adolescent or adult patients. Studies testing one or more antibiotic and reporting the diagnostic criteria used in selecting patients as well as the clinical outcomes achieved were included. No language restrictions were applied.

Data collection and analysis

Data were extracted and study reports assessed by two independent reviewers (LMB and TJMV). Authors of studies were contacted as needed to resolve any ambiguities in the study reports. The data were analyzed using the Cochrane Collaboration's RevMan 4.2.2 Software. Differences between reviewers were resolved by discussion and consensus.

Main results

Three randomized controlled trials involving a total of 622 patients aged 12 years and older diagnosed with community acquired pneumonia were included. The quality of the studies and of the reporting was variable. A variety of clinical, radiological and bacteriological diagnostic criteria and outcomes were reported. Overall there was no significant difference in the efficacy of the various antibiotics under study.

Authors' conclusions

Currently available evidence from RCTs is insufficient to make evidence-based recommendations for the choice of antibiotic to be used for the treatment of community acquired pneumonia in ambulatory patients. Pooling of study data was limited by the very low number of studies. Individual study results do not reveal significant differences in efficacy between various antibiotics and antibiotic groups. Multi-drug comparisons using similar administration schedules are needed to provide the evidence necessary for practice recommendations.

Plain language summary

Not enough evidence from trials on the comparative effects of different antibiotics for community-acquired pneumonia

Pneumonia, or infection involving the lungs, is responsible for a significant number of deaths worldwide. Pneumonia is especially life-threatening in older people and people with other illnesses that may affect the immune system (such as diabetes). Antibiotics are the most commonly used treatment for pneumonia, and these can vary in their effectiveness and adverse effects. The review studied the effects of antibiotics for patients with pneumonia acquired and treated in the community (as opposed to people acquiring pneumonia while in hospital, and/or being treated for pneumonia in hospital). There were not enough trials to compare the effects of different antibiotics for pneumonia acquired and treated in the community.