side effects of stopping b12 injections Feeling worse after Injection: Answering concerns Vitamin B12 Side Effects

Attempts to reclassify injectable B12 to a Pharmacy (P) or General Sales List (GSL) medicine have consistently met resistance from the Medicines and Healthcare products Regulatory Agency and the government, based on two key legal criteria outlined in the Human Medicines Regulations 2012 : 1

Alcohol use disorder: Alcoholism can interfere with vitamin B12 metabolism

Heffernan, M., Summers, R

Other reported effects include headaches, dizziness, nausea, and gastrointestinal discomfort, though these are less common

Its molecular target is nicotinamide N-methyltransferase (NNMT), a cytosolic S-adenosyl-L-methionine-dependent methyltransferase that converts nicotinamide to 1-methylnicotinamide, consuming SAM and releasing S-adenosylhomocysteine