“My B12 is low — can’t I just take a tablet or eat better instead of injections?”

B12 deficiency must be interpreted and treated correctly, not waved through. In a non-vegetarian with a reasonable diet, the deficiency is usually one of ABSORPTION rather than intake — classically PERNICIOUS ANAEMIA (autoimmune gastritis, loss of intrinsic factor; check the anti-intrinsic factor antibody, NICE NG239), but also coeliac disease (NICE NG20: offer coeliac serology for unexplained B12 deficiency), Crohn’s/ileal disease or resection, gastric surgery, metformin and long-term PPI, with true dietary deficiency mainly in vegans. The NEUROLOGY is what makes prompt, adequate treatment urgent: B12 deficiency causes peripheral neuropathy and SUBACUTE COMBINED DEGENERATION of the cord (dorsal columns and corticospinal tracts — paraesthesiae, sensory ataxia, unsteadiness, weakness), plus cognitive/mood and optic effects, and neurological damage may become irreversible if undertreated or delayed — so examine her face to face (not by video) and do not delay replacement while waiting for results (NG239). The core teaching for the patient who wants to "just eat better or take a tablet" is that deficiency caused by autoimmune gastritis cannot be corrected orally/dietarily and requires lifelong INTRAMUSCULAR HYDROXOCOBALAMIN (NG239) — with INTENSIVE loading when neurological features are present (BNF: 1 mg IM on alternate days until no further improvement, then 1 mg every 2 months), versus standard loading without (1 mg three times a week for 2 weeks, then every 2–3 months); oral replacement is an option for dietary deficiency. Avoid the classic pitfall of giving FOLIC ACID alone before correcting B12 (it can precipitate/worsen SACD), and check/replace iron and folate, monitor the haematological response and watch for early hypokalaemia in severe megaloblastic anaemia. Note pernicious anaemia’s autoimmune associations (thyroid, T1DM, vitiligo) and small long-term gastric-cancer risk warranting follow-up. Communicate honestly with a needle-averse patient about why injections are necessary, respecting autonomy and seeking informed acceptance rather than coercion.