Penetration of erythromycin into tonsillar tissue.

A study was carried out to investigate serum levels and tonsillar tissue penetration of erythromycin in 80 children suffering from chronic tonsillitis who had to undergo tonsillectomy. Oral erythromycin ethyl succinate (1 g twice daily) was given for the 2 days preceding surgery, the last dose scheduled for 2, 3, 4 or 6 hours before the start of the operation and the withdrawal of blood and tissue samples. The results showed that erythromycin penetrated quickly into tonsillar tissue and the levels were higher in tissue than in serum at all time points. Mean levels of erythromycin were consistently greater than the minimum inhibitory concentrations for most common Gram-positive oro-pharyngeal pathogens and H. influenzae.