Older Adults : As you age, your bodys ability to absorb B12 decreases, making older adults more susceptible to B12 deficiency
We should note that methylcobalmin does start to breakdown when exposed to light so it should be kept out of direct light
Rarely, people might have allergic reactions like hives or swelling
Your body absorbs B12 pills and injections differently
A physician investigating unexplained hypercobalaminemia will typically order some combination of the following: Complete blood count (CBC) with differential to check for abnormal red blood cell, white blood cell, or platelet counts Liver function tests (ALT, AST, ALP, bilirubin, albumin) to assess liver health Kidney function tests (creatinine, BUN, estimated GFR) to evaluate renal clearance Peripheral blood smear if a myeloproliferative disorder is suspected Abdominal imaging (ultrasound or CT) if liver or abdominal pathology is a concern Cancer-specific markers or screenings if clinical suspicion warrants them The NIH Office of Dietary Supplements fact sheet notes that observational data from a Danish registry analysis of 757,185 people found the adjusted 1-year cancer risk was 1.74 to 4.72 times higher among those with B12 above 813 pg/mL compared to those in the normal range of 203 to 813 pg/mL

Proper documentation, correct modifier use, and adherence to payer-specific rules are essential to avoid denials and audits