LUNG DEPOSITION OF BUDESONIDE INHALED VIA TURBUHALER(R) - A COMPARISON WITH TERBUTALINE SULFATE IN NORMAL SUBJECTS

We wanted to evaluate whether lung deposition of budesonide and terbutaline sulphate differs, and to determine lung deposition of budesonide inhaled at different peak inspiratory flows, through Turbuhaler(R). Lung deposition of budesonide, a lipophilic substance, and of terbutaline sulphate, a hydrophilic substance, was therefore compared, after administration via an inspiratory flow-driven, multi-dose, powder inhaler Turbuhaler(R), Astra Draco AB) to 10 healthy volunteers The radionuclide Tc-99m was used to label drug particles, and radioactivity, indicating drag deposition, was measured using a gamma camera. Budesonide was inhaled at a normal now of 58 l.min(-1) and at a slow flow of 36 l.min(-1). At the faster how, a mean+/-SD 27.7+/-9.5% of the metered dose was deposited in the hmg and at the slower Row 14.8+/-3.3% was deposited (p<0.001). Mean lung deposition of terbutaline sulphate inhaled at 57 l.min(-1) was 27+/-7.7%. We conclude that inspiratory now has an important effect on lung deposition, hut water solubility appears to have no effect.