What is Active B12 1000 derived from? Emily April 01, 2019 17:16 Updated Follow The adenosylcobalamin and methylcobalamin are synthetic. Related articles What is the best form of vitamin B12 for someone who is histamine intolerant? Can Active B12 1000 be used for children? Is Active B12 1000 suitable for vegans and vegetarians? If not, why? Potassium Deficiency Who is Active B12 with L-5MTHF lozenge intended for? Comments 0 comments Article is closed for comments.