Lymph node hyperplasia, also called reactive lymph node hyperplasia, is usually caused by drug reactions, bacterial infections, and neoplastic diseases that result in reactive hyperplasia of lymphocytes and histiocytes in the lymph nodes. 1. Drug reaction: some drugs may induce immune reaction of the body, such as the drugs used in radiotherapy and chemotherapy. Lymph nodes are important immune organs of the body, so it will lead to lymph node immune hyperplasia. 2. Bacterial infections: Bacterial, tuberculosis and fungal infections may lead to hyperplasia of nearby lymph nodes. For example, when the respiratory system is infected with viruses, the lymph nodes in the neck will proliferate. Lymph nodes with lymphoid hyperplasia caused by infection at the same time are usually accompanied by obvious pressure pain or fever. 3. Tumor disease: If malignant tumor exists in the body, with the progress of the disease, if the tumor cells have metastasis in the lymphatic system, there may also be lymph node hyperplasia. Lymph node hyperplasia caused by tumor is usually without obvious pressure and pain, hard and difficult to move. Therefore, when patients have lymph node hyperplasia, it is recommended to go to the hospital in time to find out the specific cause and give effective treatment.