Optrex Hayfever Relief 2% w/v Eye DropsOptrex Hayfever Relief 2% w/v Eye Drops provide soothing relief from 'hayfever eyes', referred to medically as seasonal allergic conjunctivitis, in adults and children over 6 years. Symptoms of this condition include itchy, watery, red or inflamed eyes and puffy eyelids. Optrex Hayfever Relief 2% w/v Eye Drops contain sodium cromoglicate, an anti-allergic medicine that stops the release of the natural substances in your eyes that can lead to an allergic reaction.