ABSTRACT
Drugs and medicinal agents administered by the inhalation route include gaseous and vaporous anesthetics, coronary vasodilators, aerosols of bronchodilators, corticosteroids, mucolytics, expectorants, antibiotics, and an increasing number of peptides and proteins where there is signifi cant nasal absorption (Cox et al., 1970; Williams, 1974; Paterson et al., 1977, 1979; Hodson et al., 1981; Lourenco and Cotromanes, 1982; Tamulinas and Leach, 2000). Concerns with the environmental affects of chlorofl uorocarbons have also led to renewed interest in dry-powder inhalers (DPIs), which, in addition, have shown promise for better tolerance and absorption for some new drugs.
