What is "hyperhomocysteinemia"

n. (context medicine English) The presence of an excessive amount of homocysteine in the blood.

Hyperhomocysteinemia or hyperhomocysteinaemia is a medical condition characterized by an abnormally high level of homocysteine in the blood, conventionally described as above 15 µmol/L.

As a consequence of the biochemical reactions in which homocysteine is involved, deficiencies of vitamin B, folic acid (vitamin B), and vitamin B can lead to high homocysteine levels.

Hyperhomocysteinemia is typically managed with vitamin B6, vitamin B9 and vitamin B12 supplementation. In individuals with genetic MTHFR deficiencies the methylated version of those 3 vitamins must be used or supplementation can make the condition worse. Taurine supplementation also has been found to reduce homocysteine levels.