Hypercalcemia is a condition characterised by elevated levels of calcium in the blood, typically defined as a serum calcium concentration greater than 2.6 mmol/L. It is clinically significant as it can lead to various complications, including renal impairment, cardiovascular issues, and neurological symptoms, necessitating prompt diagnosis and management. A common cause of hypercalcemia is primary hyperparathyroidism, which can result in significant morbidity if untreated.