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Several factors influence the choice of needle and syringe: Type of injection : Intramuscular (IM) or subcutaneous (SC) Gauge of the needle : Diameter of the needle Length of the needle : Determines the depth of injection Volume of the syringe : Determines the amount of B12 to be injected 3

People with symptoms of vitamin B12 deficiency It is a good idea for anyone with the following signs and symptoms of a vitamin B12 deficiency or pernicious anemia to consult a doctor: People with gastrointestinal issues Conditions that affect the gastrointestinal tract may affect vitamin B12 release or absorption, including: pernicious anemia, which can lead to gastric atrophy, or damage to the stomach fish tapeworm infestation bowel or pancreatic cancer folic acid deficiency overgrowth of bacteria in the small intestine diabetes thyroid disease Crohns disease celiac disease chronic pancreatitis People who have undergone gastrointestinal surgery, including weight loss, may have fewer cells necessary to secrete stomach acid and intrinsic factor
The needle and syringe recommended by your healthcare provider may look different than the needle and syringe in this Instructions for Use
Research status Mostly preclinical evidence
Unlike tablets, which have to pass through your digestive system, an injection goes straight into the bloodstream