Medications that can interfere with B 12 absorption Proton pump inhibitors, such as omeprazole/Prilosec) and lansoprazole/Prevacid commonly prescribed medications for heartburn, reflux, or ulcers Histamine H2 receptor antagonists, such as cimetidine (Tagamet), famotidine (Pepcid), and ranitidine (Zantac) also prescribed for heartburn, reflux, or ulcers Metformin, a medication for diabetes National Institutes of Health, Office of Dietary Supplements Robert H
Safety and Tolerability of the Hexadecapeptide AOD9604 in Humans, Stier H., Vos E., Kenley D., Journal (Journal of Endocrinology and Metabolism, Volume 3, Issues 12, 2013, Pages 715)
Prevalence of vitamin B12 deficiency among exclusively breast fed term infants in South India. Journal of Tropical Pediatrics 67(1) (2021): fmaa114
Spigel, D