While not common everywhere, its an option for patients who dont do well with shots or have trouble absorbing vitamin B12
Kidney conditions may reduce the kidneys ability to filter and clear vitamin B12 and its binding proteins, also leading to higher measured levels

and patients with pernicious anemia who have optic neuropathy COBALAMIN (Vitamin B12) Deficiency Causes Vegetarians (dietary deficiency) Older adults: atrophic gastritis affects 10% 30% and leads to decrease in hydrochloric acid secretion in the stomach and decreased absorption of Vitamin B12 The liver can store up to six years worth of Vitamin B12 so deficiencies are rare Effects of deficiency Megaloblastic anaemia (pernicious anaemia) Progressive demyelination of nerve cells Elevation in levels of circulating homocysteine that leads to production of defective collagen and elastin with a negative impact on arteries, bone and skin Deep vein thrombosis is associated with homocysteinemia that causes the activation of the intrinsic coagulation cascade Symptoms include fatigue, weakness, constipation, loss of appetite and weight loss Numbness, tingling of the feet imbalance, depression, confusion, dementia, poor memory and glossitis

Your prescriber will assess your progress, current dose, and any side effects before planning a safe transition