Systemic availability and lung deposition of budesonide via three different nebulizers in adults

Abstract

Budesonide is an inhaled corticosteroid widely used in the treatment of asthma. The local and systemic availability of budesonide has been determined in adults via pressurized metered-dose inhaler and dry-powder inhaler. To estimate lung deposition and systemic availability of budesonide inhalation suspension in healthy adults. Twelve adult volunteers entered an open, randomized, five-way crossover study and received the following treatments, with 1-week washout between treatments: separate 2-mg (nominal dose) budesonide doses via the Pari Inhalierboy (Inhalierboy; Pari GmbH, Starnberg, Germany), Pari LC Jet Plus (Jet Plus, Pari GmbH), and Maxin MA-2 (MA-2; Clinova Medical AB, Malmö, Sweden) jet nebulizers, 4 mg budesonide orally, and 0.5 mg budesonide intravenously. The plasma concentration of budesonide was measured up to 8 hours postadministration. Lung deposition and systemic availability of nebulized budesonide were estimated using pharmacokinetic evaluation. In this first study of the bioavailability of budesonide inhalation suspension in adults, there were no differences between nebulizers in lung deposition (14 to 16%) or systemic availability (15 to 17%) relative to the nominal budesonide dose. Relative to the actual dose inhaled (dose-to-subject), lung deposition and systemic availability were statistically significantly higher for the Jet Plus (58 and 63%, respectively) and MA-2 (59 and 64%, respectively) nebulizers than the Inhalierboy (36 and 44%, respectively). The Inhalierboy produced larger aerosol droplets than Jet Plus or MA-2 nebulizers (7-, 5-, and 3-microm mass median diameters, respectively) and delivered a higher dose-to-subject than the other two nebulizers. Relative to the nominal dose, lung deposition and systemic availability of budesonide were similar via the three nebulizers tested.