Swollen and itchy eyes, common causes are mosquito bites, allergic dermatitis, conjunctivitis, keratitis and so on. 1. Mosquito bites: mostly in summer, mosquito bites can be red, swollen, itchy eyes, generally can be relieved on their own, should avoid scratching, you can use tobramycin and other ointments to apply. 2. Allergic dermatitis: often caused by contact with allergens, such as dust, pollen, willow floss, or eating allergic foods. The redness and itching of the skin around the eyes can be treated with medicines such as cetirizine and loratadine. 3. Conjunctivitis: Inflammation of the conjunctival tissue will cause a burning sensation in the eyes, accompanied by itching, dryness, redness and swelling and other symptoms, you can use saline to rinse the eyes, and then use sodium cromoglycate eye drops to treat. 4. Keratitis: Keratitis is characterized by blurred vision, tearing, itching around the eyes, and swelling of the skin, which can be treated with drugs such as levofloxacin eye drops. If the symptoms of eye swelling and itching appear, you should consult a doctor in time to find out the cause of the disease, and choose the appropriate medication under the guidance of the physician.