methylcobalamin b12-injections-side effects What Is B12 Injection What's all the Buzz About Vitamin B12 Shots? Vitamin B12 Injection Side Effects
Description
the bad one, the calf 0.5-1 ml

Subcutaneous shots put B12 under the skin, in fatty tissue

The exact frequency depends on your individual needs, current B12 levels, and lifestyle factors

According to the DailyMed label, it is given by intramuscular or subcutaneous injection and is not for intravenous use
[DOI] [PubMed] [Google Scholar] 233.Chaudhary N, Pfluger PT

You can verify their license on the state medical board website
