Blood lithium poisoning is mainly caused by the input of excessive lithium carbonate, which leads to lithium through the ion channel into the cell, replacing sodium ions, thus reducing the excitability of the cell caused by poisoning. Clinical manifestations, patients will be mainly digestive symptoms, nausea, vomiting, abdominal pain, diarrhea, acid reflux, heartburn, and in severe cases, gastrointestinal bleeding, and there will be chest tightness, shortness of breath, palpitations, precordial discomfort, accompanied by respiratory distress, and in severe cases there will be neurological symptoms, the patient will develop ataxia. It can also lead to increased cardiac enzymes, hepatic decompensation of the liver, and increased aminotransferases. The principles of management are, first, lithium must be stopped immediately and physiologic disturbances must be corrected. Secondly, give oxygen, rehydration, can apply a large number of saline, or 5% dextrose injection for rehydration, can apply aminophylline, mannitol for asthma, reduce intracranial pressure and other treatments. Severe lithium poisoning can be treated with emetic, gastric lavage, catheterization and continuous blood purification.