The influence of seaprose on erythromycin penetration into bronchial mucus in bronchopulmonary infections.

In bronchopulmonary infections antibiotics can be combined with other drugs, called mucoactive drugs, that act to reduce the abnormal viscoelasticity of the mucus enabling a deeper penetration of more antibiotic into the mucus. Seaprose is a protease that interacts with the polymeric fibrillar structure of the bronchial mucus to shorten the long chains of mucoproteins, DNA and other macromolecules, thus reducing the viscosity of the mucus. In order to assess whether the combination of seaprose (60 mg/8 h) plus erythromycin (500 mg/8 h) allows higher antibiotic levels in sputum than erythromycin (500 mg/8 h) plus placebo, the pharmacokinetic behaviour in sputum and in blood of these two treatments was investigated in a double-blind study in two groups of twenty patients each with bronchopulmonary infections. Serum and sputum levels were determined for each patient at the first and seventh day of the two drug regimens. Statistically significant differences for peak, AUC and MRT, were observed for erythromycin between the first and last dose in the group of patients treated with seaprose plus erythromycin; moreover significant differences for these parameters were observed between the two groups. These findings indicate the presence of a pharmacokinetic synergism between seaprose and erythromycin which allows erythromycin to penetrate bronchial secretion more easily and in higher amounts, performing a sterilizing action with therapeutic advantages.