Vitamin B12 deficiency can also occur with chronic use of certain medications foe example https://pillintrip.com/medicine/exacyl. These medications can cause poor absorption of vitamin B12 and decrease its bioavailability. Medications requiring special attention include:
cimetidine and ranitidine are histamine H2 receptor antagonists;
sulfasalazine, a drug primarily used to treat inflammatory bowel disease such as Crohn’s disease or ulcerative colitis;
omeprazole, pantoprazole, lansoprazole – proton pump inhibitors;
biguanide derivatives, especially metformin, are currently quite widely used for the treatment of type II diabetes as monotherapy, in combination with other diabetes drugs,
and also with insulin. For several years, studies and publications have been conducted in which scientists warn that 10-30% of patients with type II diabetes receiving metformin have a significant decrease in the level of vitamin B12 in the blood serum. In some patients, this leads to an increase in homocysteine and methylmalonic acid (MMA) levels. The mechanism of action of metformin in reducing the absorption of vitamin B12 is not fully understood, it is believed that the reason for this may be an overgrowth of the intestinal bacterial flora in people with diabetes mellitus, which is aggravated by taking the drug due to a decrease in intestinal motility or a decrease in glucose absorption. In turn, other studies have shown a negative effect of metformin on calcium-dependent IF uptake receptors. calcium is necessary for the absorption of IF complexes and vitamin B12.
others: antibiotics, acetylsalicylic acid, carbamazepine, antacids – containing aluminum oxide and magnesium hydroxide.