Supplement for pollen allergy

[ahlam1399]

New horse seems to be suffering with a pollen allergy, doesn't do anything nasty but obviously is a tad uncomfortable for him, using a nose net which has helped so much so just wondered if any supplements people have used have helped? Many thanks

أكثر... (http://www.horseandhound.co.uk/forums/showthread.php?763040-Supplement-for-pollen-allergy&goto=newpost)