For general supplementation in at-risk groups (vegans, older adults), 25100 micrograms daily or 2000 micrograms weekly is typically sufficient
[3] Laboratory tests typically measure total B12 rather than the active form (holotranscobalamin), which can sometimes lead to misleading results
Pharmacokinetics: Cyanocobalamin is administered intranasally, orally, and parenterally, while hydroxocobalamin is administered only parenterally. Once absorbed, vitamin B12 is highly bound to transcobalamin II, a specific B-globulin carrier protein and is distributed and stored primarily in the liver as coenzyme B12. The bone marrow also stores a significant amount of the absorbed vitamin B12. This vitamin crosses the placenta and is distributed into breast milk. Enterohepatic recirculation conserves systemic stores. The half-life is about 6 days (400 days in the liver). Elimination is primarily through the bile; however, excess cyanocobalamin is excreted unchanged in the urine
Pull the whole thing out and discard straight into the sharps box Step 20
Don't let the needle touch anything once the cap is off
Rarely, an allergic reaction (rash, throat tightness) can occur