Types of B-12 Injections

If you suffer from B12-related pernicious anemia or have difficulty in absorbing B12 from the intestines, you may be required to take injections of this important nutrient. Vitamin B12 is the name given to a group of chemicals called cobalamins and is required for DNA replication, production of red blood cells, protecting the nervous system and guarding against cardiovascular disease. Individual cobalamins possess significant differences from each other, and knowing these differences makes the selection easier when choosing which is most appropriate for you.

Cyanocobalamin

• Cyanocobalamin is the most commonly injected form of B12 in the U.S. and is used to treat all forms of vitamin B12 deficiency and pernicious anemia. The popularity of cyanocobalamin is due to the hardy structure of the molecule, making it more durable and resistance to air-damage. However, this form of B12 does not occur on its own in the natural world and when ingested provides small doses of cyanide. Once in the human body, the small cyanide portion of the B12 molecule will be lost and passed out of the human body and cyanocobalamin becomes methylcobalamin. Smokers are less able to transform cyanocobalamin into methylcobalamin due to toxins and heavy metals in the liver, making this form of B12 not bioavailable to a large number of the population.

Hydroxocobalamin

• Hydroxocobalamin is one of the natural forms of vitamin B12 that is produced by bacteria and can be sterilized for injection. When compared to cyanocobalamin, this form of B12 is retained for longer periods in the body and so it reduces the need for frequent injection. Hydroxocobalamin can also be used to treat cyanide poisoning as it will attach to any cyanide molecules that it comes into contact with. Once hydroxocobalamin attaches to cyanide circulating in the blood, it becomes cyanocobalamin. In this form, the cyanide is harmlessly passed through the urine and out of the body.

Methylcobalamin

• Methylcobalamin is another natural form of B12 and is one of the active forms of the vitamin that occurs within the human body. The cyanide portion of the B12 molecule has been replaced with a methyl group and is more bioavailable to smokers who cannot transform cyanocobalamin into methylcobalamin in the liver. Methylcobalamin has been studied for the treatment of some sleep disorders. In a study published in "Psychiatry and Clinical Neuroscience" in 1999, researchers found methylcobalamin produced some limited benefit to patients suffering from sleep-wake rhythm disorders.

Adenosylcobalamin

• Adenosylcobalamin is another active form of vitamin B12 that is found in the human body and can either be supplemented orally or through injection. According to Michael Murray, N.D., author of "Encyclopedia of Natural Medicine," adenosylcobalamin has been supported by research to be more effective than cyanocobalamin in prolonging the life of mice suffering from liver cancer.