Hypomagnesemia and vitamin D deficiency complicating bisphosphonate induced hypocalcaemia

Abstract

Zolendronic acid is a potent bisphosphonate that is used to treat patients with metastatic cancer by reducing bone pain and preventing skeletal complications of bone metastasis. We reported the case of a lady suffering from metastatic breast cancer who developed seizures secondary to severe hypocalcaemia after being treated with Zolendronic acid. Hypocalcaemia was unresponsive to treatment until vitamin D and magnesium deficiencies were corrected. This case highlights the importance of taking serum magnesium and vitamin D levels in patients presenting with resistant hypocalcaemia following bisphosphonate administration, especially in those with underlying bone malignancy.