What is a b12 injection for?


Vitamin B12 injections have several beneficial effects on the human body. Most often, injections are prescribed to treat deficiencies of the vitamin in the body and can in many cases lead to a complete recovery if used correctly following a diagnosis.

Vitamin B12 and its use in treating anaemia was discovered in 1934, and since that time doctors have successfully treated patients with these injections for both chronic fatigue syndrome and anaemia.

Why Injections

This is the classic choice for Vitamin B12 treatments by physicians. Intramuscular injections are more readily absorbed by the body, having a profound and rapid effect on patients with anaemia who are not able to absorb enough of the vitamin from direct dietary sources. Doses of 1 mg per month are usually adequate and have the added benefit of reducing the chances of heart disease and stroke.

Absorption Problems

Doctors have known for some time that there is a substance in the body known as Intrinsic Factor necessary to absorb Vitamin B12 through normal digestion. Some people who don't have Intrinsic Factor for various reasons are patients who have recently had gastrointestinal surgery or those with other stomach or intestinal issues. Monthly injections of vitamin B12 can make up for the lack of Intrinsic Factor within the body.


The body's ability to properly absorb Vitamin B12 is reduced with increased age. Many older people suffer from a deficiency regardless of whether they have anaemia and naturally begin to absorb less from food intake due to a reduction in the efficiency of their stomach acid. Vitamin B12 injections can also alleviate symptoms of chronic fatigue syndrome, and some research suggests it may also help to cure progressive memory loss and lethargy.

Problems with Injections

Vitamin B12 injections are not a miracle drug by any means, as there can be complications. Not all people are cured by vitamin B12 therapy, and some doctors prescribe it for everything regardless of the diagnosis. Injections are often painful, they can sometimes cause infection or nerve damage, and too-frequent injections can cause scar tissue to form and hamper absorption.


There are oral multivitamins that can be taken instead, but it is not clear if they absorb as well as the injections. A recent new arrival on the scene, the B12 patch, is being touted now with the ability to deliver the vitamin efficiently to the body without the need for painful injections.