Vitamin B12 is water-soluble and has a low potential for harm, but more injections is not automatically better
However, the rate at which the B12 is released can be a little slower meaning that if you need B12 quickly, injections will be the better option

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

Menstrual cycles may also be altered by low levels of other vitamins, such as vitamin E, as well as by insufficient calcium or magnesium
What If: 5-Amino-1MQ Long-Term Use Scenarios What If I Use 5-Amino-1MQ for Six Months Without Baseline Labs