Tamoxifen and hypercalcaemia

The present case demonstrates the importance of close observation, also of serum calcium, when initiating tamoxifen therapy, especially in patients with known osseous metastases. Hypercalcaemia should also be considered as a possible cause of CNS symptoms in patients newly started on endocrine treatment. Hydration with saline is the first step in the management of hypercalcaemia. In patients with a serum calcium level > 3.50 mmol/l (serum ionised calcium approximately 2.00 mmol/l) hydration should be combined with bisphosphonates.