I just don't get why vets either don't know or won't tell people that tear (and siliva) stains are caused by bacteria. In the 12 years of Frosty's life so far, he has had it 3 times. Eveytime he has had Amoxicilin tabs for a week and it is gone! Of course the hair then has to either grow out or be cut off to get white again. It can come from almost any small infection or irritation. Eye infections (lack of tearducts would cause the eyes to be so irritated they could be infected easily), teething, ear infections, tonsils, allergies that irritate, etc.....One of his started when he had his teeth cleaned at the vets which spreads bateria.
Obviously it helps to keep the hair out of the eyes and keep the little goobers out of the corners of the eye and frequent face washing. I use the little pads that come in a jar and are damp with a solution for cleaning under his eyes, and a mustasche or human eyebrow comb to keep the area clean.
All the wonder products for bleaching the red out or covering it up would not be necessary if the cause is cured. Not curing the problem sure makes a market for products.
I realize the danger of using too many anti-biotics and would not do it often. I haven't had to. The first vet Frosty had 12 years ago wanted him to have Terramyicin in his drinking water continually! Forget that! That was with his first staining, which was when he was teething. I am so glad I found out early how to take care of him so he always has a pretty white face. After I did, I had to find a new vet and then when the staining happened after the teeth cleaning I went to 3 different vets in the same office (it took 3 mo., none of them believed me it would work) before finally getting one that said, O.K. I'll give him the Amoxicilin. Within days the hair was starting to grow out white. If I wasn't convinced before that, I sure was then.
Dee