Maternal Vitamin B12 Status During Pregnancy and Its Association With Outcomes of Pregnancy and Health of the Offspring: A Systematic Review and Implications for Policy in India. Frontiers in Endocrinology vol
67 In 2018, a meta-analysis of four RCTs found significant benefits for herpetic neuralgia of locally injected methyl-B12, 1 mg on 6 days per week for 24 weeks
Scalp injection requires shorter needles (46mm) due to thinner subcutaneous tissue depth
Some people, particularly those who were severely deficient, report a sudden improvement in energy, focus, or mood within 24 to 72 hours
Protocols using doses below 0.5mg daily may require 1620 weeks to demonstrate observable improvement
However, specific policies and support mechanisms vary across different NHS trusts and Integrated Care Boards (ICBs)