Explanations and therapies for penicillin failure in streptococcal pharyngitis.

A disturbing trend toward penicillin failure has developed in the treatment of streptococcal pharyngitis in some parts of the United States and abroad. A variety of explanations has been proposed to account for these penicillin-treatment failures. With the resurgence of serious complications from streptococcal infection, successful bacteriologic eradication has regained importance. In communities with a high incidence of penicillin failures, alternative antimicrobials should be considered. Cephalosporins, amoxicillin/clavulanate, and the extended-spectrum macrolides represent logical options under such clinical circumstances.