A little while ago, my ten-year-old DSH cat had a really watery eye. I thought he had something in it because of all the watering and the fact that he was keeping it half closed. The third eyelid was slightly across at times, and there was a faint bit of pinkness in the white part. I was prepared to call the vet next day, but the eye cleared up overnight. I thought nothing more of it until five days later, when the same problem appeared in the opposite eye. Again, it cleared up in 24 hours. He had no other symptoms, and is active and eating well. It was ragweed season at the time, plus very dry and dusty because of drought; could it have been an allergic reaction to dust and/or pollen?
Yes, it could have been allergies. Without a direct examination, though, that’s only a guess. If the problem recurs again, I would have a veterinarian check it out.