Dear Jenny,
It sounds as if she may have a mild allergy, most probably to grass pollen or another pollen blowing around in the wind. Other possibilities are a spray cleaner or cosmetic in your house.
These things are not necessarily something in your garden or house, so the best thing to do is improve the dog's general immunity so she does not have a tendency to react to allergens in her environment.
Research shows that increasing omega 3 fatty acids can reduce allergic symptoms, so plenty of fish oil, fish or coconut milk/oil in the diet can help.
I hope I don't sound like a broken record (or CD) but removing carbohydrate from the diet helps the liver work effectively. Traditional Chinese Medicine agrees with this, saying, "the liver opens through the eye". So reducing carbs (dried food, pasta, bread) from the diet and replacing them with raw meat, raw bone and vegies will detox the liver and improve allergy eyes.
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