Vitamin B12 is an essential vitamin as it helps in the production of DNA and RNA, metabolism of proteins and fats, etc. This vitamin also aids in the proper functioning of the nervous system and controls the wear and tear of the nerve cells.

Vitamin B12, like all the other B vitamins, is a water soluble vitamin and cannot be stored in the body. Apart from the natural sources this essential nutrient can be taken in the form of vitamin supplements like pills, injections and tonics. One such supplement is the B12 injections, which are also known as
or simply
cobalamin injections

Recommended Dosage for Vitamin B12 Injections

# A dosage of
1-2 mg daily
is prescribed especially while treating neurological disorders and other nutritional deficiencies. This is typically considered as a large dose. In case of missed dose, it's better to reschedule the dosage (discuss with your physician) rather than taking two doses together.

# Most physicians prescribe B12 injection dosage as:
1 mg per dose after every 2 days
10 times
. Maintenance is
1 mg
every month.

# The dose for children may vary according to their age, as prescribed by the pediatrician. The dosage may range between
0.4 mcg and 1.8 mcg
on a daily basis. For children above 14 years of age, the dose is
2.4 mcg

# Vitamin B12 shots are administered intramuscularly or under the skin, known as subcutaneous injections. The normal dosage as recommended by doctors is approximately
6-70 mg, every week for 3 weeks


There are many advantages of taking shots, since they are directly assimilated in the bloodstream and provide instant effects. These injections not only cure the vitamin deficiency, but also help in treating various health conditions. Here are some benefits of this nutritional supplement:
  • One of the most common benefits of vitamin injections is immediate increase of energy.
  • This vitamin also helps in the formation of red blood cells and assists in the proper functioning of the cardiovascular and nervous systems.
  • This injection in administered to patients who are suffering from pernicious and megaloblastic anemia. These health disorders occur when the body is not able to absorb vitamin B12 completely.
  • Taking vitamin B12 for weight loss is a very effective method since it increases the rate of metabolism which results in the burning of more calories, therefore keeping a check on weight gain. Hence, it is popularly known as metabolism booster.
  • Hydroxocobalamin, which is a form of vitamin B12 is an effective remedy for curing cyanide poisoning.
  • Certain studies have proved that injecting this vitamin to children suffering from autism have shown certain improvements in their behavior.
  • Vitamin B12 supplements are also known to fight against chronic fatigue syndrome.
  • Another benefit is that the risk of heart and other cardiovascular diseases is relatively reduced due to this nutrient. This vitamin also helps lower cholesterol and reduces the risk of breast cancer, dementia and Alzheimer's disease.
Side Effects

The dose for vitamin B12 injections is determined by a physician and is administered accordingly. An overdose of this supplement can result in side effects. Some of the side effects are common whereas some of them can be serious, depending on the dose. Some of the common side effects are given as under. They are usually mild in nature and will go away after some time.
  • Swelling and pain at the site of the injection
  • Appearance of skin rashes
  • A feeling of nausea and vomiting sensation
  • Headaches, ranging from mild to severe
  • Slight pain in the joints
  • Stomach upset and diarrhea
Some of the severe side effects, in case of an overdose, are given as below:
  • Frequent urination, especially during the night
  • Muscle weakness and cramps
  • Heart palpitations and breathlessness
  • Appearance of small, red sores in the arms and legs, which may cause itching
  • Feeling tired or fatigued even after doing minor work
  • Pain in the muscles, especially in the legs
  • Mild chest pain
  • Rapid and unexplained weight gain
  • Tight feeling in the chest
  • Difficulty while swallowing
  • A feeling of numbness in the entire body.
  • Hypokalemia or low potassium
  • Peripheral vascular thrombosis
  • Gout
  • Polycythemia vera
Vitamin B12 injections or any other supplement must be taken only under the guidance of a health care provider to avoid any possible effects of a heavy dose. In case of an overdose, visit the doctor immediately who may provide remedial relief for the problem.

Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.