The terms of the Montreal Protocol have eliminated chlorofluorocarbons (CFCs) and other ozone-depleting agents from commercial use, with the exemption of their use as propellants in metered-dose inhalers. Two new propellants have been approved for CFC substitutes: hydrofluoroalkane (HFA)-134a and HFA-227. An extensive safety program was conducted by the International Pharmaceutical Aerosol Cons...

STUDY OBJECTIVE To determine whether a spacer device designed as a valved holding chamber with a flow signal increases the efficacy of the long-acting beta(2)-agonist, salmeterol, in patients who use incorrect technique with metered-dose inhaler (MDI) alone. DESIGN Double-blind, randomized, placebo-controlled study. SETTING University hospital outpatient rooms. PATIENTS Twenty adult outpa...

A multi-center, double-blind, 90-day study compared an ipratropium bromide metered-dose inhaler (40 microgram four times a day) with a metaproterenol metered-dose inhaler (1,500 micrograms four times a day) in 164 patients with asthma; of the 144 patients who completed the study, 71 received ipratropium and 73 received metaproterenol. Our results suggest that both drugs were equally effective b...

Inhaled glucocorticoids such as beclomethasone dipropionate, which are used in the treatment of asthma, may be associated with systemic adverse effects. To determine whether any systemic absorption following the inhalation of beclomethasone was a result of drug being absorbed from the lung (inhaled fraction) or the gastrointestinal tract (swallowed fraction), we studied normal subjects after th...

Three doses of fenoterol were administered by metered-dose inhaler to 20 adult subjects with asthma in order to determine the optimal dose for routine administration. Inhaled doses of 100 micrograms, 200 micrograms, and 400 micrograms of fenoterol with isoproterenol and placebo controls were administered in a randomized double-blind crossover regimen. We found that 200 micrograms of fenoterol b...

Among the devices employed for aerosol generation (metered-dose inhalers, nebulizers, and dry powder inhalers) only metered-dose inhalers and nebulizers are routinely employed for aerosol delivery to mechanically ventilated patients. The ventilator circuit and artificial airway were previously thought to be major barriers to effective aerosol delivery to mechanically ventilated patients. In the...

A correlation equation for the mass median aerodynamic diameter (MMAD) of the aerosol emitted by solution metered dose inhalers (MDIs) is presented. A content equivalent diameter is defined and used to describe aerosols generated by evaporating metered dose inhaler sprays. A large set of cascade impaction data is analyzed, and the MMAD and geometric standard deviation is calculated for each dat...

Doctors from 34 practices participated in an audit study which examined inhaler technique in up to 20 of their patients. A new scoring system, applicable to all forms of device, was used. Although the majority of the 422 patients (63%) was using metered dose inhalers, a broad range of other devices was included; most frequently Rotahalers (15%) and spacer devices (9%). For analysis, technique s...