Erythromycin in the treatment of streptococcal infections.

In a number of well-designed comparison studies since 1958, erythromycin has proved highly effective in the treatment of both streptococcal pharyngitis and skin infections. Of the two formulations most often prescribed, the estolate salt is better absorbed and achieves higher tissue concentrations than does the ethylsuccinate salt. For these reasons and based on results of the published clinical studies, the appropriate daily dosage for erythromycin estolate is 20 to 30 mg/kg/day and that for erythromycin ethylsuccinate is 40 mg/kg/day. Erythromycin estolate may be given in two, three or four daily doses in the treatment of streptococcal pharyngitis with efficacy rates equal to or better than that achieved with penicillin V. Erythromycin ethylsuccinate is as efficacious as penicillin V when given in three or four daily doses. Treatment of streptococcal pharyngitis should be for 10 days. Recent studies in the treatment of streptococcal skin infections have shown erythromycin to be superior to penicillin. This superiority may be due to increasing numbers of penicillin-resistant staphylococci found in these streptococcal skin lesions. Dosage and frequency of administration of erythromycin in the treatment of streptococcal skin infections is similar to that for the treatment for streptococcal pharyngitis. However, b.i.d. administration has not been well-established in the skin infection studies. Treatment should be given for 7 to 10 days. In conclusion erythromycin is a safe and effective antibiotic for the treatment of streptococcal pharyngitis. Penicillin remains the antibiotic of choice for these infections, but erythromycin is an effective alternate when penicillin allergy is suspected. The appropriate therapy for streptococcal skin infections is less clear.(ABSTRACT TRUNCATED AT 250 WORDS)