Abstract: Cisplatin is widely used in clinic. It is often used in combination with other chemotherapeutic drugs in the treatment of lung cancer, head and neck cancer, esophageal cancer, gynecological and urinary system cancer. Hyponatremia caused by cisplatin chemotherapy is uncommon in clinic, with the incidence of 4%-10%. Severe hyponatremia is rare. Special attention should be paid to the occurrence of hyponatremia in the course of chemotherapy with platinum-containing chemotherapy regimen. The symptoms of the disease are atypical and the mechanism is different. It needs timely and accurate diagnosis and effective treatment. This paper reports a case of severe hyponatremia in gestational trophoblastic neoplasm during chemotherapy. The etiology was analyzed and treatment suggestions were put forward.

Key words: Cisplatin, Drug therapy, combination, Gestational trophoblastic disease, Hyponatremia, Syndrome of inappropriate secretion of antidiuretic hormone