can b12 injections make you feel worse How Long Does It Take Vitamin to Work? B12 Shots Side Effects And

The upper arm, specifically the back or outer portion where you cannot easily reach, is technically suitable but difficult to self-inject without assistance

This method is effective for people needing quick results or dealing with long-term deficiencies

Judy J

Target Population The target population of this economic analysis was patients aged 18 years and older with confirmed vitamin B12 deficiency

UK guidance (MHRA and NICE) advises checking B12 levels in patients on metformin who develop symptoms of deficiency (anaemia, neuropathy) and considering periodic monitoring in those on long-term therapy

Research findings are preliminary and do not imply safety or efficacy.