What laboratory tests to order to fully evaluate for possible vitamin B12 deficiency

This article was first published on July 11, 2024. It was last reviewed, updated, or edited on July 11, 2024. One of my outpatients, an older adult with a depressive disorder, hypertension, dyslipidemia, and mild, unexplained, cognitive impairment, among other problems. She had been previously identified as having vitamin B12 deficiency and, for a long…