The concentration of tobramycin in bronchial secretions.

Fifteen noninfected patients received three consecutive doses of tobramycin (1.7 mg/kg intramuscularly). Serum and bronchial secretions were obtained during bronchoscopy. Microbiologic assay demonstrated that bronchial secretions containing tobramycin produced inappropriately small zone sizes when compared with serum. Also, it was shown that bronchial secretions frequently do achieve therapeutic concentrations of tobramycin at this dosage level and route of administration.