Evaluation of allergic etiology in perennial rhinitis.

: In 197 patients with perennial rhinitis, 49 patients (24.9%) were found to be allergic to perennial inhalant allergens, 37 patients (18.8%) allergic to seasonal allergens, 52 patients (26.4%) had food intolerance, 12 patients (6.6%) showed evidence of nasal infection, and in 46 patients (23.3%) etiology was undetermined.