The therapeutic activity and tolerability of sobrerol, a muco-active agent, were evaluated in 30 children (aged 5-10 years) with secretory otitis media. The drug was administered once daily by inhalation for 10 days consecutively at a dose of 40 mg/3 ml. Clinical assessments showed a significant improvement in the objective measures together with good tolerability. Moreover, sobrerol was shown to improve impedance values; this is an important aspect of the modifications induced by this drug in diseases involving the ear.