A phase 2 trial exploring the effects of high‐dose (10,000 IU/day) vitamin D₃ in breast cancer patients with bone metastases

Abstract

Daily doses of 10,000 IU vitamin D(3) for 4 months appear safe in patients without comorbid conditions causing hypersensitivity to vitamin D. Treatment reduced inappropriately elevated parathyroid hormone levels, presumably caused by long-term bisphosphonate use. There did not appear to be a significant palliative benefit nor any significant change in bone resorption.