With an oral supplement, the B12 needs to be absorbed through your digestive system first before getting to your blood, which takes a lot longer
How to Administer a B12 injection to Yourself There are two ways to self-inject vitamin B12: Subcutaneously, or just below the skin, and intramuscularly, which goes directly into the muscle, says Foxx
Q: Are there any peptides I should absolutely avoid
[2] When to Seek Further Medical Advice About B12 Patients should maintain regular contact with their GP or healthcare team throughout B12 treatment, but certain situations warrant urgent medical review
Blood cell production typically begins improving within 35 days, haemoglobin rises over 12 months, whilst neurological recovery may take several months