Vaccination Injections Vaccine administration follows different coding rules than therapeutic injections
Hydroxocobalamin 1mg intramuscular injections reactivate metabolic pathways after chronic deficiency, potentially causing temporary symptoms during adjustment Common side effects include injection site pain, headaches, and nausea, typically resolving within 2472 hours Rapid red blood cell production may increase demand for folate and iron, occasionally creating relative deficiencies in these co-factors Serious reactions requiring urgent assessment include difficulty breathing, chest pain, severe weakness, or progressive neurological symptoms Recovery follows a predictable pattern: blood cell improvement within 35 days, haemoglobin normalisation over 12 months, neurological recovery potentially taking several months Table of Contents Why Do I Feel Worse After My B12 Injection
Unlike vitamin B12 deficiency, which produces well-recognised neurological and haematological problems, hypercobalaminaemia (elevated B12) is typically asymptomatic
Persistent fatigue, mental fog, or low mood arent things you have to just live with theyre signs your body may be low on a vital nutrient