Whole body tissue distribution of [14C]-erythromycin in the guinea pig. An autoradiographic study

The distribution of 14C-labelled erythromycin following intravenous administration to the guinea pig has been studied by whole body autoradiographic technique. Erythromycin was quickly and extensively distributed throughout the body although penetration into some compartments like brain, spinal cord or vitreous body was limited. High radioactivity concentrations were detected in kidney, liver, lung, upper respiratory tract and in bone marrow. Lung tissue and bone marrow were characterized by delayed elimination of erythromycin. The prenetration of erythromycin into skin could be shown. 24 h after the administration of erythromycin still high amounts of radioactivity were detected in the faeces.