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
Start with our peptide cost calculator to plan your budget, then use our specialized calculators for precise protocols
If you suspect your B12 supplement is causing problems, discuss alternative formulations or routes of administration with your healthcare provider rather than simply stopping therapy
Who should consider vitamin B12 shots
