Allergens rhymes with:
antigens, belgians, cajuns, carcinogens, collegians, dungeons, engine's, engines, georgians, hodgens, hudgens, hydrogens, imagines, legions, margins, neurosurgeons, norwegians, pathogens, pigeon's, pigeons, region's, regions, religion's, religions, sturgeons, surgeon's, surgeons, theologians, trajan's, trojans, virgin's, virgins