B12 Injection Dosage and Frequency: 7 Essential Guidelines for Adults Liv Hospital Feeling low on energy lately? B12 injections can give your body the boost it's craving. This little vitamin packs a punch and is loved for: Increased energy & reduced fatigue Vitamin B12 Injectable City Cat Pharmacy is available for clients of City Cat Vet Clinic only. Wow guys, you've been gate keeping!! Got my first B12 injection last week and it's like I am awake for the first time since having kids 20 years ago It's