If you’re having vitamin B12 deficiency symptoms your physician could recommend supplementation in the form of injections.  There are plenty of reasons why they give Vitamin B12 injections instead of oral B12. B12 is absorbed in small intestines specifically in ileum with the help of the intrinsic factor, an enzyme produced by the linings of the stomach. When you take a medicine orally, it takes some time for it to get absorbed into your circulation due to various factors that can interfere with the absorption such as the presence of food in the stomach, gastric acidity, and transit time.

Vitamin B12 is commonly administered intramuscularly in people with pernicious anemia and gastrointestinal disorders that renders the inability to produce the intrinsic factor needed for absorption of B12, making the oral B12 supplementation useless. And then their vitamin B12 stores will ran out in time and they will soon experience B12 deficiency symptoms as their body struggles to keep the body functioning. The therapy for vitamin B12 deficiency is done by giving sufficient B12 doses not just to supply the patient’s daily needs of the vitamin, but also to refill liver stores of vitamin B12. This is given daily, weekly or according to the doctor until the symptoms subside. Patients who no longer have the ability to absorb vitamin B12 properly are generally receiving intramuscular injection monthly for life. Vitamin B12 can be administered in large quantity intravenously but only in cases of cyanide poisoning.

Recently, vitamin B12 shots are getting popular due to its energy boosting effects that many entertainers, politicians, celebrities have used them. It is administered directly into the bloodstream making the effects work rapidly. It boosts energy by increasing metabolic activity, the process of burning calories for energy. There are people use B12 Injections for weight loss but in some studies found no evidence that support vitamin B12 cause weight loss. Vitamin B12 shots side effects are generally minor mostly pain at the injection site, headaches, nausea and diarrhea. But if symptoms of allergy occur, you should contact a physician as soon as possible.