What medications can lower B12?

Common medications that deplete Vitamin B12 include stomach acid reducers (PPIs like omeprazole, H2 blockers like famotidine), the diabetes drug metformin, and anti-gout drug colchicine, with long-term use being a concern as they interfere with B12 absorption, leading to potential deficiency symptoms like fatigue or nerve issues. Other culprits are certain antiseizure meds, antibiotics, corticosteroids, and alcohol.

What drugs cause B12 deficiency?

Several common medications can cause B12 deficiency by interfering with its absorption, primarily acid-reducing drugs (like PPIs: omeprazole; H2 blockers: famotidine) and metformin (for diabetes), as they reduce stomach acid or interfere with calcium needed for absorption, respectively. Other culprits include some anti-seizure drugs (phenytoin, carbamazepine), colchicine, and even long-term nitrous oxide use, with higher doses or longer use increasing risk.
 

Which medication lowers B12?

Taking omeprazole (Prilosec), lansoprazole (Prevacid) or other stomach acid-reducing medicine might lower the body's ability to absorb vitamin B-12. Vitamin C (ascorbic acid) supplements. Taking vitamin B-12 with vitamin C might lower the available amount of vitamin B-12 in the body.

Can B12 cause headaches?

Yes, Vitamin B12 can cause headaches, both from a deficiency (low levels) and sometimes from taking very high doses of supplements, leading to side effects like headache, dizziness, or fatigue. Deficiency can cause headaches due to nerve irritation or reduced oxygen to the brain, while excess B12 (especially injections) might trigger headaches, nausea, or weakness, though it's generally considered safe.
 

What makes your B12 level go down?

Vitamin B12 deficiency is caused by either not eating enough B12 (common in vegan/vegetarian diets) or, more frequently, by poor absorption due to autoimmune conditions (pernicious anemia), stomach/intestinal problems (Crohn's, celiac disease, surgery), certain medications (metformin, antacids), or alcoholism, with older adults also being at higher risk.
 

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What illness causes low vitamin B12?

B12 deficiency is often caused by pernicious anemia (an autoimmune issue blocking absorption), gastrointestinal disorders (like Crohn's, celiac, or atrophic gastritis), stomach/intestinal surgery (bariatric, gastrectomy), genetic conditions, chronic pancreatitis, or even a vegan diet or alcoholism, all leading to poor absorption or intake of this vital vitamin.
 

What stops the body from absorbing vitamin B12?

Vitamin B12 absorption is blocked by factors reducing stomach acid (like PPIs, H2 blockers, alcohol, aging), conditions damaging stomach/intestine lining (Crohn's, Celiac, gastritis, pernicious anemia, surgery), lack of intrinsic factor, certain medications (metformin, nitrous oxide), and dietary gaps (veganism without supplements). These issues prevent B12 from separating from food, binding to intrinsic factor, or reaching the ileum for absorption.
 

How do you feel when your B12 is low?

When your B12 is low, you might feel extremely tired, weak, or have a lack of energy, along with neurological issues like tingling/numbness (pins and needles) in your hands and feet, balance problems, and "brain fog" (memory/confusion). Other common signs include a sore, red tongue, pale skin, mood changes (depression/irritability), shortness of breath, and digestive issues. These symptoms can develop slowly and worsen over time, impacting both your body and mind. 

What medications affect the absorption of vitamin B12?

Common medicines affecting vitamin B12 absorption include Proton Pump Inhibitors (PPIs), H2-receptor antagonists (H2RAs), and the diabetes drug Metformin, all reducing stomach acid or altering gut function needed for B12 release and absorption, plus antiseizure drugs like phenytoin, anti-gout meds like colchicine, and some antibiotics. Chronic use can lead to deficiency, causing fatigue, nerve issues, or anemia, requiring monitoring by a doctor, says The Economic Times and the NHS. 

What food is highest in B12?

The foods highest in Vitamin B12 are organ meats (like liver and kidney) and shellfish (especially clams), offering thousands of percent of the daily value in small servings, with fortified cereals, dairy, fish (salmon, tuna, sardines), and eggs also being excellent sources. For vegans, fortified foods like nutritional yeast and plant milks are key, as B12 is naturally found in animal products.
 

What do you crave when your B12 is low?

B12 deficiency can cause specific food cravings, particularly for meat, fish, or eggs, as your body seeks sources of the vitamin, and may also lead to sugar cravings due to its role in serotonin and energy regulation, but it can also manifest as pica (craving non-food items like ice or even bleach in severe cases). These cravings signal your body trying to correct a nutrient imbalance, but clinical testing is needed for a proper diagnosis, as emotional factors also drive cravings. 

Does omeprazole lower B12?

Yes, long-term use of omeprazole (Prilosec) and other proton pump inhibitors (PPIs) can lead to vitamin B12 deficiency because they reduce stomach acid, which is needed to release B12 from food for absorption. This decreased absorption can cause fatigue, weakness, and neurological issues, so it's important to talk to a doctor about monitoring B12 levels with chronic PPI use. 

Can low B12 cause dizziness?

Yes, low vitamin B12 can absolutely cause dizziness, often due to anemia (reduced oxygen-carrying red blood cells) or nerve damage, leading to lightheadedness, imbalance, and feeling unsteady, especially with exertion or when standing up. Because B12 is crucial for brain and nerve function, deficiency impacts the central nervous system, causing neurological symptoms like dizziness alongside fatigue and weakness.
 

What are the neurological symptoms of B12 deficiency?

Vitamin B12 deficiency causes a wide range of neurological issues, including tingling/numbness (pins and needles), balance/coordination problems (ataxia), memory loss, confusion, depression, vision disturbances, and muscle weakness, often due to damage to the spinal cord (subacute combined degeneration) and peripheral nerves, which can become permanent if untreated. 

What medications conflict with B12?

Several common medications, especially acid-reducing drugs (PPIs, H2 blockers) and the diabetes drug Metformin, significantly lower vitamin B12 levels by impairing its absorption from food, along with antiseizure meds, certain antibiotics, and anti-gout drugs like Colchicine, requiring potential supplementation or monitoring.
 

How common is B12 deficiency?

Vitamin B12 deficiency is surprisingly common, affecting around 6% of people under 60 and up to 20% of those over 60 in the U.S. and UK, with even higher rates in developing nations, often overlooked despite serious symptoms like fatigue and neurological issues, especially in older adults, vegans, vegetarians, or those with digestive issues or taking certain meds. 

Which drug depletes B12?

There is general consensus that gastric acid–lowering drugs, including proton pump inhibitors (PPIs) and H2-receptor antagonists (H2RAs), and the antidiabetes drug metformin can reduce circulating vitamin B-12 concentrations with prolonged use.

What medications decrease B12 levels?

Summary: As summarized in the table provided, vitamin B12 (cobalamin) absorption and utilization by the body can be compromised with the chronic use of certain medications which include: colchicine, chloramphenicol, ethanol, histamine 2 receptor antagonists (H2RA), metformin, and proton pump inhibitors (PPI).

Can medications cause low B12?

Some types of medicine can lead to a reduction in the amount of vitamin B12 in your body. Examples include: proton pump inhibitors (PPIs) metformin.

What are the facial signs of B12 deficiency?

Cutaneous manifestations associated with vitamin B12 deficiency are skin hyperpigmentation, vitiligo, angular stomatitis, and hair changes. A diagnosis of vitamin B12 deficiency is often overlooked in its early stages because these signs are not specific to vitamin B12 deficiency alone.

What are the two main causes of B12 deficiency?

Lack of vitamin B12 in your diet: People who don't eat enough foods that have vitamin B12 or don't eat foods fortified with B12 can develop a deficiency. Gastritis: Gastritis is inflammation of the stomach lining, and it's a common cause of vitamin B12 deficiency.

What is the fastest way to fix B12 deficiency?

The fastest way to recover from B12 deficiency, especially severe cases, is through B12 injections (cobalamin), often starting with frequent shots (e.g., every other day for a couple of weeks) to rapidly replenish stores, particularly if neurological symptoms are present, followed by oral supplements or less frequent injections, depending on the underlying cause. While dietary changes and high-dose oral supplements help, injections bypass absorption issues for quicker correction. 

Why would B12 suddenly drop?

Some stomach conditions or stomach operations can prevent the absorption of enough vitamin B12. For example, a gastrectomy (a surgical procedure where part of your stomach is removed) increases your risk of developing a vitamin B12 deficiency.

What are the first signs of B12 deficiency?

Early B12 deficiency signs often include fatigue, weakness, pale or yellowish skin, shortness of breath, headaches, and a sore, smooth tongue, but can also manifest as neurological issues like tingling (pins and needles) and memory problems, alongside mood changes (depression, irritability). Because symptoms develop slowly and mimic other conditions, prompt medical evaluation with a blood test is crucial for proper diagnosis and to prevent potentially irreversible nerve damage, notes the NHS, the Cleveland Clinic, and WebMD. 

What is the disease where you can't absorb B12?

Pernicious anemia is a relatively rare autoimmune disorder that causes diminishment in dietary vitamin B12 absorption, resulting in B12 deficiency and subsequent megaloblastic anemia. It affects people of all ages worldwide, particularly those over 60.