In my experience if your dogs eyes are very drippy, this will dry them up.  But, if you're dogs eyes are very dry, they did harm to my Miracle's eyes, drying them out even too much.  But, a great treat to help with tear stains and over producing tears in the eyes.  IN MY OPINION WITH MY EXPERIENCE. I AM NOT A VETERINARIAN, YOU CAN CONTACT MANUFACTURER FOR MORE HELP.