Discloses is a passive transdermal delivery device comprising: a backing substrate and an active agent layer, wherein the active agent layer is substantially anhydrous and oil-free and includes as thickening agent a cellulose derivative and an ionizable active agent, wherein the ionizable active agent is electrically neutral in the active agent layer and dissociates into an ionized active agent upon contacting an aqueous medium and is selected from the group comprising: a beta-adrenergic agonist, Procaterol HCI, a salt of a carboxylic acid-containing active agent, and L-ascorbic acid or a derivative thereof. Also disclosed is a topical formulation comprising the composition and a use of the composition for the manufacture of a medicament for treating an obstructive respiratory ailment.
