Swelling underneath the inside of the eyes may refer to lower eyelid edema, which is related to blepharitis, allergic conjunctivitis, acute dacryocystitis and other causes. 1. Blepharitis: also known as wheals, the eyelid glands of the eyes are infected by bacteria and develop suppurative lesions, resulting in redness, swelling and pain of the eyelids, causing swelling underneath the inside of the eyes. 2. Allergic conjunctivitis: the conjunctival tissue is stimulated by allergens and an inflammatory reaction occurs, which releases inflammatory factors and affects the permeability of blood vessels, leading to the leakage of fluids in the blood into the tissue interstitial space and the emergence of edema, resulting in the above symptoms. 3. Acute dacryocystitis: blockage caused by nasolacrimal duct infection, resulting in impaired circulation of the lacrimal gland, abscess in the area of the lacrimal sac, accompanied by redness, swelling, pain, etc., resulting in swelling below the inside of the eye. If your eyes are swollen, you need to consult a doctor for diagnosis, clarify the cause of the disease, treat the symptoms, pay attention to a light diet, avoid spicy and stimulating foods, reduce the number of late nights, rest more, and ensure that you get a good night’s sleep.