All content on Lab Tests Online has been reviewed and approved by our Editorial Review Board.
At a Glance
Why Get Tested?
To determine if you have a vitamin D deficiency; if you are receiving vitamin D supplementation, to determine if it is adequate
When to Get Tested?
When you have an abnormal calcium, phosphorus, and/or parathyroid hormone level; when you have evidence of bone disease or bone weakness; when you are at high risk of deficiency or a healthcare practitioner suspects that you might have a vitamin D deficiency; prior to starting drug treatment for osteoporosis; periodically to monitor treatment of vitamin D deficiency
A blood sample drawn from a vein in your arm
Test Preparation Needed?