Chemotherapy is a common treatment for stomach cancer, but it may cause some side effects, including swollen eyelids. This phenomenon may be because chemotherapy drugs have toxic side effects on the body, causing fluid to accumulate in the tissues. In addition, chemotherapy may also cause damage to the body`s immune system, making eye tissues susceptible to infection. If the eyelid swelling is severe or accompanied by other discomfort symptoms, it is recommended to seek medical attention in time. The doctor may examine the condition of the eyes and rule out other possible causes, such as eye infection or allergic reaction. Then, depending on the specific situation, appropriate treatment measures may be given, such as antibiotic eye drops, anti-allergic eye drops, or local cold compresses. It is worth noting that the side effects of chemotherapy generally gradually decrease as the treatment progresses, but each person`s situation may be different and should be treated according to individual circumstances. During chemotherapy, eating a balanced diet, getting enough rest, maintaining good oral hygiene, and avoiding contact with substances that may cause sensitivity can also help reduce the extent of side effects. If you are worried or have other discomfort symptoms, it is recommended to consult a doctor for professional advice.