Compounded Methylcobalamin (Vitamin B12) Injection, 5mg mL Vitamin B 12 Injectable Solution 1000mcg ML 250ml Vial Vitamin B 12 Injection for Animals, 3000 mcg mL, 100 mL Vial Prescription Medication for Pets B 12 (Methylcobalamin) Therapy MedClub by Dr Jenn B12 Methylcobalamin vs Hydroxocobalamin The difference between in clinic B12 injections vs over the counter. There are many forms of vitamin B12, the form used at La Bella is Methylcobalamin. The CYANOCOBALAMIN Vitamin B12 Injectable Solution for Horses, 5000 mcg, 100 mL Easy Refills Chewy Rx