Swollen bags under the eyes in the morning may be caused by physiological factors such as lack of sleep and drinking a lot of water before going to bed, or it may be caused by diseases such as insect bite reaction and granuloma. 1. Physiological factors: If the night sleep time is too short, or drink a lot of water before going to bed, it will lead to the next day, the bags under the eyes become swollen, is the normal situation. 2. Insect bite reaction: insect bite reaction is an allergic reaction to insect bites, if the skin under the eyes is bitten by mosquitoes at night, swelling and itching will occur locally. 3. granuloma: granuloma is an acute purulent inflammation of the eyelid glands, usually caused by staphylococcal infections, patients will appear localized redness, swelling, heat and pain and other symptoms, which can also lead to swelling of the bags under the eyes. Swollen eyes in the morning for more reasons, if there is no other discomfort, mostly considered to be physiological factors. On the contrary, it is considered to be caused by diseases, and should be examined by a doctor.