There were 4 groups:

Fatty acid-based supplement: 2 tablets per day, which contained 550 milligrams of fatty acids (the specific types were not specified), 0.21 milligrams of vitamin B6, 20 milligrams of Perilla frutescens, and 200 milligrams of licorice
Intranasal corticosteroids: 1 puff in each nostril twice a day
Intranasal corticosteroids plus fatty acid-based supplement
Placebo intranasal spray

Allergic rhinitis severity was assessed by endoscopic evaluation, and subjective symptoms were reported by the participants using 2 questionnaires.

Disease severity and symptoms improved in the groups that took the supplement, compared to the corticosteroids-only and placebo groups. There were no differences between the 2 groups that took the supplement.

A fatty acid-based supplement shows promise for allergic rhinitis Original paper