Eye Allergies: How It Works, Explained Simply

Video Transcript

Eye allergies happen when the surface of the eye reacts to something harmless in the environment, like pollen, dust mites, mould, or pet dander. The conjunctiva is packed with immune cells called mast cells. When an allergen lands on the eye, these cells release histamine and other chemicals. Histamine makes nearby blood vessels widen and leak slightly, which produces redness, swelling, watering, and above all, itching. Itching is the hallmark. If your eyes are red but not itchy, an allergy is less likely to be the explanation. Allergies typically affect both eyes together, and often come with sneezing, a runny nose, or a blocked nose. Some allergies are seasonal, following tree and grass pollen. Others run all year, from dust mites or pets indoors. Reducing exposure helps. Wraparound sunglasses outdoors, showering after being outside, keeping windows closed on high pollen days, and washing bedding regularly. Cool compresses and lubricating drops rinse allergens away and soothe. Antihistamine or mast cell stabiliser eye drops are common treatments. Try not to rub, since rubbing releases more histamine and makes the itch worse. This video is for general education only. It is not medical advice. Ask your eye doctor what's right for you.