Delighted I received my B12. I don't see a use by date on them or am I missing it? The Feline Essentials B12 has definitely improved my cat's appetite and appearance in recovering from Pancreatitis. I started using the B12 last week in combination with the CATalyst product that I've been How to Give a B12 Injection: Step By Step Instructions Compounded Hydroxocobalamin (Vitamin B12) Injection Purpose of FitShot Injection HomeKit at VITAstir Clinic Vitamin Injections B12 Shots IV Therapy Calcium Gluconate and Vitamin D3 & B12 Injection Best Price for Animal Health