Allergic conjunctivitis presents like bacterial conjunctivitis or pink eye, but the causes and treatments are different. Allergic conjunctivitis usually happens when the eyes come into contact with an allergen, a substance that makes the body’s immune system overreact. The immune system kicks into high gear, producing an inflammatory response in the eyes, and tears to flush out any foreign object. The eye becomes sore and inflamed, and the body releases histamine. The blood vessels dilate, irritating the nerve endings.

1. Seasonal Allergic Conjunctivitis

Seasonal allergies and hay fever can produce itchy, watery red eyes, especially when the pollen count is high. The eyelids may become swollen and painful. With this type of allergic conjunctivitis, it’s especially important to refrain from rubbing your eyes, as any trace of pollen on your fingers can spread further into your eyes and cause more irritation. If conjunctivitis results from pollen, there will likely be other common seasonal allergy symptoms such as sneezing, an itchy, blocked, or a runny nose, and itchy, watery eyes.

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