PRECAUTIONS: Vitamin B12 deficiency that is allowed to progress for longer than 3 months may produce permanent degenerative lesions of the spinal cord
doi:10.1136/emj.2003.006130 Alcohol-Medication Interactions: Potentially dangerous mixes | National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Its not very new but still relevant
the MHRA advises checking vitamin B12 levels if deficiency is suspected and considering periodic monitoring in those with risk factors [6] Chronic alcohol consumption can damage the gastric mucosa and impair absorption Nitrous oxide exposure (including recreational use) can inactivate vitamin B12 in the body, causing functional deficiency and neurological symptoms If you experience symptoms such as unexplained fatigue, pale skin, shortness of breath, neurological symptoms (tingling, numbness, balance problems), mood changes, or cognitive difficulties, contact your GP promptly
The body needs more time to restore B12 stores before showing any improvement when starting from a very low initial B12 level