Edema once summer comes may be caused by reactive edema, organic lesions and other reasons. 1. Reactive edema: Usually when the temperature is higher in summer, it will lead to vasodilatation of skin blood vessels, and body fluids will penetrate the dilated blood vessels, leading to accumulation of subcutaneous tissues, thus forming edema. 2. Organic lesions: Usually when the temperature is higher in summer, the patient’s sweating will increase, so fluid intake will also increase. If the patient has kidney problems, such as glomerulonephritis, the glomerular filtration rate will be impaired, and a large amount of fluid intake can not be discharged, which may also lead to edema in the summer. It is recommended that patients who experience edema in the summer should seek medical attention and regular treatment under the guidance of a professional doctor.