Eyepack
The reason dog tear stains are so hard to eradicate is that they are a visible symptom of a deeper systemic problem. They are caused by a variety of factors, one of which is a bacterial infection in the dog's system. That’s why, if you want to get rid of those dark tear stains under your dogs eyes, wiping them away is only the first step; unless you boost your best friend’s immunity to fight the infection, the bacteria that cause the problem will persist and so will the stains.