RADIOTRACER EVALUATION OF THE DEPOSITION OF DRUG PARTICLES INHALED FROM A NEW POWDER INHALER

Deposition of 99mTc-labelled particles of disodium cromoglycate in the human respiratory tract after inhalation either from the conventional metered dose aerosol or from the new Ingelheim powder inhaler (FO II) was compared. Fractional deposition in the whole lung area, in the upper airways and in the device was measured using a gamma camera. Eight healthy informed volunteers participated in the inhalation test. The lung deposition of the inhaled drug was about 9% using the conventional aerosol actuator with the short plastic mouthpiece whereas, using the Ingelheim powder inhaler, on average 20% deposition in the whole lung area was achieved. In addition, with the Ingelheim inhaler drug particles seemed to be deposited in the more peripheral parts of the respiratory tract. The upper airway deposition was also reduced with the Ingelheim powder inhaler. On the other hand, a larger fraction of the drug dose was retained in the Ingelheim inhaler than in the aerosol actuator. © 1990.