Policy Number 

Policy Name 

Policy Description 

CP.MP.121 

Homocysteine Testing 

Homocysteine is a nonproteinogenic amino acid generated during the conversion of methionine to cysteine. Mutations of the enzymes within the biochemical pathways that regulate homeostatic homocysteine levels are associated with risk factors for various diseases such as venous thromboembolic disease.18,19 Supplementation of folic acid, vitamin B6, and vitamin B12 are known to modulate homocysteine levels due to the interplay between the folate cycle and metabolism. This policy describes the medical necessity requirements for testing levels of homocysteine.