Following up the results obtained in a previous work testing Positional Rhinomanometry in normal subjects, the authors performed this test in subjects affected with specific nasal hyperreactivity. The aim was to offer an objective evaluation of decubitus-caused variations in air flow resistance through the nasal cavities. Thirty subjects suffering from allergic rhinitis (18 from seasonal and 12 perennial allergic rhinitis) underwent Anterior Active Rhinomanometry during the intercritical period of the disease. Tests were performed in the seated, supine positions homolateral and contralateral to the fossa in question. The positional tests show a marked difference between normality and specific hyperreactivity as a consequence of paradoxical responses. Moreover it can indicate the greater increase in nasal resistance, expression of a clear disreactivity of the cavernous tissue stimulated by variations in posture and found mostly in the perennial allergic rhinitis subjects.