People without a deficiency should not take megadoses of B12
Conclusion Learning how to give B12 injections can be a valuable skill for healthcare professionals and non-medics alike

Normal vital signs (blood pressure, heart rate, respiratory rate, temperature) and body mass index (BMI) between 18 and 30 kg/m 2 Suboptimal vitamin B12 status (deficient to borderline 200300 pg/mL), defined as serum B12 levels within the lower end of the reference range (234894 pg/mL) Able to provide informed written consent Able to comply with study procedures and follow-up visits as outlined in the protocol 2.2.2 Exclusion criteria Known hypersensitivity or allergy to oral vitamin B12 supplements or any of its components Known history of cobalt allergy or sensitivity Severe malabsorption syndromes, including pernicious anemia or intestinal disorders affecting vitamin B12 absorption Current use of acetaminophen, nonsteroidal anti-inflammatory drugs, antibiotics, antacids, proton pump inhibitors (PPIs), multivitamins, or nutritional supplements containing vitamin B12 History of gastric bypass surgery or other procedures that significantly alter GI anatomy or function Significant renal impairment (estimated glomerular filtration rate [eGFR] 0.05) Supplementary Table 1

The sixth coordination site, the center of reactivity, is variable, being a cyano group (-CN), a hydroxyl group (-OH), a methyl group (-CH3) or a 5-deoxyadenosyl group (here the C5 atom of the deoxyribose forms the covalent bond with Co), respectively, to yield the four B12 forms mentioned above
All treatments carried out by NMC Registered experienced Nurse Prescriber with 24 hour emergency contact number
Downtime with this procedure is typically shorter, and the cost is considerably lower