Antibiotic Therapy in Community-Acquired Pneumonia: Switch and Step Down Therapy

Hugh A. Cassiere, MD, Winthrop University Hospital


Medscape General Medicine. 1998;1(3) 

In This Article

Traditional Recommendations

Most textbooks that address issues concerning treatment of community-acquired pneumonia discuss the "antibiotics of choice" for specifically identified pathogens and stress the need for intravenous antibiotics delivered in-hospital.[10,11,12,13,14] The administration of intravenous antibiotics for community-acquired pneumonia is based upon the concept that to ensure eradication of the causative pathogen, a high concentration of antibiotic in the blood and tissue is initially required. Recommendations on the duration of therapy or when, if at all, oral agents should be initiated, is left to clinical judgment -- "when the patient clinically improves."

For example, in pneumococcal pneumonia, treatment with intravenous penicillin is recommended for at least 7 to 10 days, or until the patient has remained afebrile for a minimum of 5 days.[10] Longer duration of therapy is traditionally recommended for the treatment of atypical pneumonia. A 3 week course of antibiotic therapy is suggested for treating Legionella pneumonia -- 4 grams of erythromycin per day until "an adequate clinical response is seen." Then the dose may be decreased to 2 grams per day.[10] Recommendations for the treatment of pneumonia caused by beta-hemolytic streptococci include 2 to 4 weeks of intravenous penicillin.[10]

The ambiguity of these recommendations may partially account for wide practice variation observed in the management of community-acquired pneumonia.