Piriton allergy tablets are used to treat the allergic symptoms of hayfever and other allergies the active ingredient is chlorphenamine maleate an antihistamine which can help to relieve the symptoms of some allergies and itchy skin rashes it can be used to treat the itchiness redness swelling tenderness and irritation that can be caused by hayfever and other allergies eg pet house dust mite and mould spore allergies nettle rash and hives skin allergies and dermatitis p