Sixteen adult patients suffering from severe chronic non-
allergic rhinitis with nasal
vasoconstrictor abuse for more than a year, received, under local anaesthesia, an intranasal spray of
capsaicin (3.3 x 10(-3) mol), the pungent agent in hot pepper, once weekly for 5 weeks. The subjective intensity of their
nasal obstruction, rhinorrhoea and
sneezing frequency were evaluated throughout the study and the vascular effects of
capsaicin on the nasal mucosa were recorded by anterior rhinomanometry and
laser Doppler flowmetry.
Calcitonin gene-related peptide (CGRP) is a
vasodilator agent present in sensory nerves and may play a major role in the vascular component of
neurogenic inflammation. Therefore, the nasal mucosa content of CGRP-like immunoreactivity (CGRP-LI) was determined by radioimmunoassay in biopsies obtained before and after the
capsaicin treatment. Intra-nasal
capsaicin application evoked a larger vascular response in patients with
rhinitis than in controls (P less than 0.05). Both nasal vascular responses and subjective discomfort following
capsaicin were markedly reduced after the fifth application (P less than 0.01). In parallel, a 50% reduction of the CGRP-LI content in the nasal biopsies was observed. All symptoms were significantly improved throughout a 6 month follow-up period. No significant side-effects occurred and weaning from
nasal vasoconstrictor agents was possible. Both the subjective symptom score and objective measurements of vascular reactivity suggest that repeated intra-nasal
capsaicin application could be beneficial for patients with chronic
rhinitis, possibly by reducing hyperreactive nasal reflexes.