In 11 patients, in whom a lung lobe or whole lung was to be resected, a single dose of 1.6 mg inhaled budesonide was given pre-operatively. In 9 of them, concentrations of the drug in both lung tissue and blood plasma were measured. Budesonide concentrations in lung tissue, at least 90 min after dosage, were 2.1-8.9 nmol kg-1. Concentrations in blood plasma (0.27-1.1 nmol kg-1) were 1/8th of those in lung tissue.