In a recent review (2018) by the famous Cochrane Institute, it was reported that studies which had been published on this topic only provided very low-quality evidence that oral B12 is as efficacious as intramuscular B12
28-Day Rule the full 28-day rule, what shortens the window, and when to discard Multi-Dose Vial Safety: How Many Draws from Bac Water
Supplements simply give that system an extra nudge
In contrast, when bound to transcobalamin II, the half-life is significantly shorter, approximately 1.5 hours, although the final plasma curves for both forms yield similar half-life values of around 9.3 to 9.8 days due to the rapid reappearance of the radiocobalt label bound to transcobalamin I
Most comprehensive single-document peptide reference 18 peptides with dose, frequency, duration, timing, reconstitution Protocols shown here are based on publicly disclosed information from Jay Campbell