Cyanocobalamin × Pantoprazole

Pantoprazole reduces gastric acidity and B12 release from food. With long-term therapy, B12 deficiency risk is reported, similar to other PPIs.

Fatigue, pallor, paraesthesias in hands and feet, gait instability, memory decline. Develops over 2–4 years of unrecognised therapy.

On long-term pantoprazole (over 2 years), check B12 yearly. Cyanocobalamin can be given regardless of acidity (passive diffusion absorption at high doses). For sustained acid suppression, consider dose reduction or periodic breaks.