Giving vitamin B12 parenterally? Which electrolyte should you check first? Answer: Potassium. And why does it matter? Because rapid correction of severe B12 deficiency can trigger a surge in Vitamin B12 Atlantic inj 1000 mcg mL (1000 mcg mL x 10 mL) for Vit B12 Deficiency & Anaemia Lazada Singapore B!2 Inject Kit: Package Insert Prescribing Information Vitamin B12 Injection 0.1%,Nutritional drugs,Bullvet,Bullvet Cyanocobalamin Injection (AK Vibisone Vitamin B 12), 10,000 mcg 10 mL 10 cs