The AAFPs evidence-based clinical review states directly: Oral administration of high-dose vitamin B12 (1 to 2 mg daily) is as effective as intramuscular administration for correcting anemia and neurologic symptoms in patients with B12 deficiency (Langan RC, Goodbred AJ, American Family Physician, 2017)
When anemia is present, i.e., low levels of the oxygen carrier hemoglobin, it results in impaired oxygen delivery, which affects not only cognitive function but also physical performance and perception of fatigue and tiredness
Free radicals, metals and antioxidants in oxidative stress-induced cancer
The most common adverse events are gastrointestinal-related, such as nausea, vomiting, constipation, stomach pain, and diarrhea
Do not leave syringes at room temperature
Murphy G