From the Guidelines
No, vitamin B12 (cobalamin) is not the same as hydroxocobalamin, though they are closely related. Vitamin B12 is a general term for a group of compounds called cobalamins, while hydroxocobalamin is a specific form of vitamin B12. Hydroxocobalamin has a hydroxyl group (-OH) attached to the cobalt atom at its center, making it a particular variant of cobalamin. Other forms of vitamin B12 include methylcobalamin, adenosylcobalamin, and cyanocobalamin.
Key Differences and Uses
- Hydroxocobalamin is commonly used as a medication to treat vitamin B12 deficiency and is often preferred for injections because it remains in the body longer than other forms.
- It's also used as an antidote for cyanide poisoning because it can bind to cyanide molecules, forming cyanocobalamin which is then excreted, as recommended by the American Heart Association 1.
- All forms of vitamin B12 are essential for DNA synthesis, red blood cell formation, and neurological function, but they differ slightly in their chemical structure and how they're processed in the body.
Clinical Recommendations
- The use of hydroxocobalamin for cyanide poisoning is supported by recent guidelines, which recommend its administration due to its effectiveness and safety profile compared to other treatments like sodium nitrite 1.
- The administration of hydroxocobalamin, along with other treatments such as sodium thiosulfate and 100% oxygen, is considered a reasonable approach for managing cyanide poisoning, based on the latest clinical guidelines 1.
From the FDA Drug Label
Vitamin B12 is essential to growth, cell reproduction, hematopoiesis, nucleoprotein and myelin synthesis. Hydroxocobalamin shares the cobalamin molecular structure with cyanocobalamin.
Vitamin B12, also known as cobalamin, is not the same as hydroxocobalamin in the sense that they are different forms of the vitamin. However, hydroxocobalamin is a form of vitamin B12. They share the same molecular structure, with hydroxocobalamin being one of the forms of cobalamin 2, 2.
- Hydroxocobalamin is a specific type of vitamin B12.
- Vitamin B12 is a broader term that encompasses different forms, including hydroxocobalamin and cyanocobalamin.
From the Research
Definition and Relationship
- Vitamin B12, also known as cobalamin, is a complex organometallic compound with a cobalt ion at its core [ 3 ].
- Hydroxocobalamin is a form of vitamin B12 [ 3 ].
- Hydroxocobalamin is used as an antidote for cyanide poisoning [ 3 , 4 ].
Chemical and Pharmacological Properties
- Hydroxocobalamin has a high affinity for cyanide and can bind to it, forming a non-toxic compound [ 5 ].
- Hydroxocobalamin is a precursor of vitamin B12 [ 3 ].
- Hydroxocobalamin can be used to treat acute cyanide poisoning [ 6 ].