Abstract
The nasal mucosal blood flow was determined by means of the 133Xe wash-out method in an early stage of acute rhinitis and in health and the effect of a topical decongestant (oxymetazoline) was evaluated. During an early stage of acute rhinitis, a statistically significant increase of blood flow was found. The topical decongestant in therapeutically recommended doses decreased the blood flow significantly in acute rhinitis as well as in healthy subjects. The effect was more pronounced in acute rhinitis. The effect of oxymetazoline was dose dependent and a statistically significant decrease was found in doses of about 1/50 of the therapeutically recommended. The clinical implication is that it might be possible to reduce the dose of the decongestant in order to minimize the negative side effect of a decreased blood flow.