He continued to say that for people with B12 deficiency, parenteral supplementation (ie not through the mouth/digestive system) therefore is a useless and expensive treatment, and if you still want it the NHS should not pay for it, you should pay for it yourself

Patients who have undergone gastric banding should be aware of the following signs that may indicate falling B12 levels and warrant prompt blood testing: Neurological symptoms: Tingling, numbness, or 'pins and needles' in the hands or feet Difficulty with balance or coordination Memory problems, difficulty concentrating, or 'brain fog' Mood changes, including low mood or irritability Haematological symptoms: Persistent fatigue or weakness disproportionate to activity levels Breathlessness on mild exertion Pallor or a slightly yellowish tinge to the skin Other indicators: A sore, smooth, or inflamed tongue (glossitis) Mouth ulcers occurring frequently It is important to recognise that some of these symptoms particularly fatigue and low mood are non-specific and may overlap with other post-operative nutritional deficiencies, such as iron or vitamin D deficiency
Can I take it orally
However, injections focus only on one nutrient
Special situations and common questions What not to do after a B12 injection if youre on blood thinners If you take warfarin, a direct oral anticoagulant, or other medications that reduce clotting, tell the clinician before the shot