Gastrointestinal symptoms (more common with oral preparations): Mild nausea or upset stomach Diarrhoea (typically with very high doses) Other effects: Headache, particularly when treatment is first initiated Dizziness or light-headedness Skin reactions such as mild rash or itching Temporary reddish discolouration of urine (chromaturia) after hydroxocobalamin injections, which is harmless It is important to note that many symptoms attributed to B12 supplementation may actually represent the body's response to correcting a deficiency
It's available over the counter in concentrations of 2% and 5%, most commonly as a liquid or foam applied directly to the scalp
Most people absorb enough natural B12 that they dont have to worry about additional supplements, but for those with poor nutrition, stomach problems or cancer, B12 can be hard for the body to process
It really depends on what type of wrong youre talking about
For patients on established B12 injection therapy, monitoring is based primarily on clinical response and haematological parameters rather than routine serum B12 measurements, which may remain very high without indicating harm or overtreatment