Definition

1. Noun:
   • A form of vitamin B12, specifically cyanocobalamin or hydroxocobalamin, which is essential for the formation of red blood cells and the proper functioning of the nervous system. Its administration corrects the deficiency that causes pernicious anemia.

Usage

• This is a highly specific, technical medical term. It is primarily used in clinical, pharmaceutical, and biochemical contexts to refer to the therapeutic form of vitamin B12 used for a specific disease.
• In modern general and even most medical communication, the terms "vitamin B12," "cyanocobalamin," or "hydroxocobalamin" are more commonly used.

Examples

• Noun:
  • The patient's treatment regimen included regular injections of the antipernicious anemia factor.
  • Historically, the discovery of the antipernicious anemia factor in liver extract was a major breakthrough in medicine.

Advanced Usage

• The term is often found in historical medical texts or in discussions of the discovery and isolation of vitamins.
• It precisely denotes the substance's function (countering pernicious anemia) rather than just its chemical structure.

Variants and Related Words

• Vitamin B12 (noun): The general name for the group of cobalamin compounds, including the antipernicious anemia factor.
• Cyanocobalamin (noun): A common synthetic form of vitamin B12 used in supplements and treatments, often synonymous with the antipernicious anemia factor.
• Hydroxocobalamin (noun): Another form of vitamin B12 often used in injections, also functioning as the antipernicious anemia factor.
• Extrinsic factor (noun): An older term for vitamin B12 itself, distinguishing it from the produced in the stomach which is needed for its absorption.

Synonyms

• Cobalamin: The core chemical term for compounds with vitamin B12 activity.
• Vitamin B12: The common nutritional and dietary term.

Notes on Meaning

• The term is functionally defined. It does not refer to a different substance from vitamin B12 but specifically highlights its therapeutic role in treating pernicious anemia, a condition caused by an inability to absorb the vitamin.

Noun

1. a B vitamin that is used to treat pernicious anemia