my dog has black eye gunk, red eye corners

[greyhoundlover]

Hi. My name is Melissa and this is the first time I have posted here. I have two of the sweetest greyhounds you could ever meet, ages 3 and 5. We adopted our most recent addition in July, and he has always had lots of black eye gunk in his eyes, and the corners of his eyes themselves are very red. The whites of his eyes are not red. I had him on a raw diet for several months but recently switched him to Canidae, which has no grains or corn, and he's had less problems with his ears. It took forever and lots of different medications from the vet to get him over the ear infection (with yucky brown ear gunk) that he came with. When we first got him, I asked about his eyes, got some drops from the vet, used the whole bottle even though it didn't help, and was told it was probably allergies. I'm worried it could be something else, but before I go to the vet looking like the dog hypochondriac that I am, any opinions would be welcome. Thanks.