For most people, yes, when it is medically appropriate and supervised
The dose depends on whats in it
B12 injections help the body produce healthy red blood cells, improving overall vitality and reducing feelings of fatigue
So easy to order my B12 from Vitastir
this is the most common cause of vitamin B12 deficiency in the UK a lack of these vitamins in your diet this is uncommon but can happen if you have a vegan diet and do not take vitamin B12 supplements or eat foods fortified with vitamin B12, follow a fad diet or have a generally poor diet for a long time medicine certain medicines, including anticonvulsants and proton pump inhibitors (PPIs), can affect how much of these vitamins your body absorbs Vitamin B12 and folate deficiency are more common in older people, affecting around 1 in 10 people aged 75 or over and 1 in 20 people aged 65 to 74

Conditions include alcoholic liver disease, viral hepatitis, cirrhosis, and primary or metastatic liver cancer Renal dysfunction : Impaired kidney function reduces B12 elimination, causing accumulation even with normal intake Haematological conditions : Myeloproliferative neoplasms, chronic myeloid leukaemia, polycythaemia vera, and hypereosinophilic syndrome increase transcobalamin production, elevating total serum B12 Laboratory interference : Macro-B12 (immunoglobulin-bound B12) and assay interference can cause spuriously elevated results without true excess In clinical practice, unexplained hypercobalaminaemia should prompt investigation for underlying disease, particularly in patients without obvious supplementation history