OBJECTIVE: To measure the droplet size distribution of a nicotine pressurized metered-dose inhaler using a nicotine in ethanol solution formulation with hydrofluoroalkane as propellant.
MATERIALS AND METHODS: Sizing was performed at room temperature by multistage liquid impinger and quartz crystal impactor.
RESULTS: The mass median aerodynamic diameter of the nicotine aerosol produced was measured at 1.6 μm by multistage liquid impinger and 1.5 μm by quartz crystal impactor.
CONCLUSIONS: The inhaler formulation used produces a microaerosol of sufficiently fine droplet size that mimics the puff-by-puff pulmonary arterial bolus nicotine delivery of tobacco smoke. The absence of combustion products such as heat, carcinogens and carbon monoxide permits safer nicotine delivery via the inhaler than is possible via smoked tobacco.