Multi-dose bacteriostatic water vials (such as 30 ml presentations) are a US-centric product and are not routinely stocked or licensed as a standard diluent in the UK
injectable use is research-only
Anecdotal reports from athletic forums describe doses ranging from 250500 mcg twice daily, often exceeding research-validated ranges by 36
Selected lots are independently verified by Janoshik Analytical (Czech Republic) and published on the Janoshik public portal
Ribaldone D, Fagoonee S, Astegiano M, Durazzo M, Morgando A, Sprujevnik T, Giordanino C, Baronio M, De Angelis C, Saracco G, Pellicano R (2019) Rifabutin-based rescue therapy for Helicobacter pylori eradication: a long-term prospective study in a large cohort of difficult-to-treat patients
You'll probably encounter two types of vitamin B12--Methylcobalamin and cyanocobalamin