(The blueing only came to mind because I use to show a grey pony and I'd have to wash him and then put blueing on him to get the stains out of his fur and get him nice and bright.
Constituted by a blend of natural, organic herbs that have anti-inflammatory, anti-bacterial and anti-fungal properties, Naturally Tearfree Canine balances out the PH and acidity in the saliva and tears, both of which are excretions that stainfur.