In vitro comparison of nebulised budesonide (Pulmicort Respules®) and beclomethasone dipropionate (Clenil® per Aerosol)

This study compared the in vitro performance of two inhaled corticosteroid products for nebulisation, Pulmicort Respules® (budesonide 0.5 mg/mL) and Clenil® per Aerosol (beclomethasone dipropionate (BDP) 0.4 mg/mL). Each product was used in combination with three different nebulisers (2 mL/test, 5 min run time) and the dose to the lungs was determined according to standard methods. The shape of the suspended particles in each product was studied using scanning electron microscopy (SEM). Overall, a higher fine particle dose was achieved with Pulmicort Respules® versus Clenil® per Aerosol, with estimated dose to the lungs of 8–14 and 3–6% of nominal dose, respectively. SEM showed that budesonide particles were small, typically ∼2–3 μm in diameter, whereas those of BDP were needle-shaped and up to ∼10 μm long. The more favourable particle shape and size of suspended budesonide may explain the higher fine particle dose with Pulmicort Respules® versus Clenil® per Aerosol.