Swelling and pain when blinking in the area of the left eyelid is firstly considered to be a mosquito bite or allergy phenomenon. Secondly, because of the silkworm part close to the lower eyelid, so also consider that may be related to the lower eyelid disease. If after hot compresses, rest and other general ways can not be relieved, should consult a doctor in time, clear condition after active treatment. 1, mosquito bites: such as mosquitoes, mites, midges, fleas and other insects biting the left eyelid part of the silkworms, can cause localized swelling, blinking when the performance of the pain, but also often accompanied by itching, rashes, blisters, etc., the patient can be used with alkaline soapy water wash wounds, if no improvement, can be medical treatment, follow the doctor’s instructions to use Glycerin lotion or hydrocortisone cream treatment; 2, allergy: common dust mites, animal hair, pollen, or cosmetics, skin care products, etc. contact with the left eye silkworm parts, causing local allergies, swelling, pain, may be accompanied by increased eye discharge, blinking pain is more obvious. You can use boric acid solution wet compresses under the guidance of a doctor, or local application of mometasone furoate cream, and in severe cases, you can take oral loratadine, benadryl and other anti-allergy medication; 3, acute wheal: that is, acute blepharitis, manifested in local redness, swelling, fever, pain, blinking may exacerbate the pain, and even hard knots, pus points, broken, congestion and other phenomena. First of all, you can apply local hot compresses to relieve the pain, or use tobramycin ophthalmic ointment, levofloxacin eye drops, erythromycin ophthalmic ointment and other medications as prescribed by the doctor, and then cut and drain the pus and then use medications if the abscess is serious. 4, other diseases: such as blepharophimosis, eyelid boils, blepharitis, dacryoarthritis, and other ophthalmic diseases, it may also affect the left eyelid part of the silkworm, resulting in swelling and pain when blinking, and the patient can go to the hospital in time. Patients can go to the hospital and have the doctor choose the appropriate medication or surgical treatment according to the cause of the disease, and at the same time, keep the eye clean and avoid rubbing the eye with your hands. Regardless of the cause, during the period of swelling and pain relief, you should avoid rubbing and scratching the swollen and painful parts of the left eye, so as not to cause local bacterial infection or aggravate the symptoms of infection. At the same time, you should also pay attention to avoid stimulation of the affected area, stop using eye cosmetics, irritating skin care products. If you need to go out, you can wear eyeglasses to protect the affected area and prevent dust, pollen, cold air, etc. from irritating the swollen and painful area of your left eye.