b12 injections better than tablets Vitamin vs. Supplements: Which Works Best? B12 Shots vs. IV Infusions:
Description
Cyanocobalamin is more commonly found in oral supplements and fortified foods, and while it is effective for many people, some practitioners prefer hydroxocobalamin for injections due to its natural form and longer retention

You can review related indexed studies on PubMed, where the compound appears under both its development code and its full descriptive name

Vitamin B12 injections also positively affect mood

Lancet 387 (10026), 13771396