B12 deficiency with neurological symptoms

Demyelination of the posterior and lateral columns of the spinal cord in B12 deficiency. Presents with paraesthesia, impaired deep sensation, ataxia, and cognitive decline. Neurological symptoms can appear before anaemia and may be the first sign of deficiency.

ICD-10 E53.81 drug

Also known as: Subacute combined degeneration of the spinal cord

Drugs used for this condition

ACyanocobalaminFirst line · Vitamins. Haemopoietic stimulantsIn subacute combined degeneration and other neurological features of B12 deficiency, high-dose parenteral cyanocobalamin or hydroxocobalamin is the only disease-modifying therapy. Maximal recovery occurs in the first 6 months, before irreversible axonal degeneration develops. With late treatment, neurological deficit may partially persist. Early suspicion of B12 deficiency prompts B12 and homocysteine testing without delaying therapy until results return.

How to read tiers A–F

Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit