Distribution of lymecycline in interstitial fluid and paranasal sinus mucosa. An experimental and clinical study.

A comparison between different methods of determining the levels of lymecycline in tissue is presented. The drug levels have been compared with those registered, during the steady state condition, in interstitial fluid obtained from subcutaneously implated tissue cages in rabbits. The 'tissue piece diffusion method' developed is reproducible; it allows antibiotic levels to be determined in minute pieces of tissues, and it seems to measure the total diffusable drug in the interstitial fluid phase. This method was employed in the analyses of lymecycline concentrations in the maxillary sinus mucosa in 12 patients, and it demonstrated a good penetration into the tissue. The level reached was well above the Minimal Inhibitory Concentration of most bacteria causing maxillary sinusitis.