When should I consider referring a patient with hypercalcaemia to secondary care?

Refer all people with hypercalcaemia to an appropriate specialist, with the urgency and route of referral depending on the calcium level severity and clinical picture, unless hypercalcaemia is mild, asymptomatic, and a reversible cause has been identified and, when removed, calcium has returned to normal ¹.

If the person has severe hypercalcaemia (corrected calcium greater than 3.5 mmol/L) or severe symptoms, arrange emergency admission to hospital for further assessment and management such as intravenous fluids and bisphosphonate therapy ¹.

For moderate hypercalcaemia (corrected calcium 3–3.5 mmol/L) or if the person is symptomatic, consider immediate same-day referral to hospital and/or liaise with the appropriate specialist depending on the clinical picture ¹.

If hypercalcaemia is mild (corrected calcium greater than 2.6 but less than 3 mmol/L) and asymptomatic, make a full clinical assessment, arrange initial investigations, and refer to the appropriate specialty if a cause is not identified or if calcium remains high after correction ¹.

In cases of hypercalcaemia associated with known malignancy or suspected underlying cause, liaise with the relevant specialist managing their care, and consider urgent referral if calcium levels are high or symptoms are severe ¹.

Patients with hypercalcaemia of malignancy or other complex cases may require specialist management, including intravenous treatment, medication review, and treatment of underlying conditions, with referral to secondary care as appropriate ¹.