High blood calcium is mostly seen in hyperparathyroidism, bone metastatic cancer, oversupplementation of calcium, etc. It needs further diagnosis and symptomatic treatment. 1. Hyperparathyroidism: excessive secretion of parathyroid hormone can lead to elevated blood calcium, which may cause symptoms such as irritability, drowsiness and memory loss, etc. Thyroid function and thyroid ultrasound can be checked to confirm the diagnosis. 2. Bone metastatic cancer: In patients with bone metastatic cancer, due to the destruction of a large amount of bone by cancer cells, calcium in bones is released into blood, resulting in elevated blood calcium, which may be accompanied by symptoms such as pain and easy to fracture, etc. Patients can go to the hospital for further examination to confirm the diagnosis. 3. Excessive calcium supplementation: such as excessive vitamin D supplementation, long-term large doses of calcium preparations, etc., may cause elevated blood calcium, and should be supplemented appropriately in normal times, and should not be taken in large doses for a long period of time. If you have symptoms of high blood calcium, you need to go to the hospital for further examination and diagnosis, so as to clarify the cause of the disease and treat the symptoms.