Tests For Vitamin Levels
Blood tests for vitamin levels may be ordered as part of a routine physical examination or for patients exhibiting symptoms such as fatigue. For example, many patients now have their vitamin D levels checked as part of the bloodwork ordered during annual checkups. Tests for vitamin levels are done with a blood sample taken from a vein. If the results show the patient is low in a particular vitamin, doctors will normally prescribe high-dose supplements for a few weeks or months. The patient will be given another blood test after that time to check if their levels are within the normal range. In cases where vitamin levels are extremely low, doctors may give a series of vitamin injections; this is especially common in the case of vitamin B deficiencies.