Nebulizer possibilities and limitations.

The ban of chlorofluorocarbon (CFC) propellants in metered dose inhalers (MDIs) gives rise to many alternatives and innovations: 1. CFC substitution by non-CFC propellants in MDIs. 2. battery driven miniaturized mechanical and piezoelectric nebulizers 3. revitalization of hand driven pocket nebulizers 4. self actuated dry powder inhalers (DPI's). All devices can be used with or without spacers. The choice for solid or liquid particles, e.g. powder or droplet aerosols, will also depend on the drug properties and the availability on the market for aerosol use. The nebulizer device will be chosen according to the medical need (emergency or long term treatment), the technical alternatives available in different countries, the possibility of patient cooperation (children, severely ill patients), and last not least marketing strategies and costs. The bronchial circulation is an important distribution system for medicine deposited by aerosol routes in the lung.