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How Your Antacid Drug Is Making You Sick (Part A)


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Note: this is the fourth article in a series about heartburn and GERD. If you haven’t done so already, you’ll want to read Part I, Part II and Part III before reading this article.

Believe it or not, stomach acid isn’t there just to punish you for eating Indian food. Acid is in the stomach because it’s supposed to be there. It is found in all vertebrates. And while it isn’t necessary for life, it is certainly required for health.

Most people have no idea how many vital roles stomach acid plays in our bodies. Such misunderstanding is perpetuated by drug companies who continue to insist that stomach acid is not essential.

Meanwhile, millions of people around the world are taking acid suppressing drugs that not only fail to address the underlying causes of heartburn and GERD, but put them at risk of serious (and even life-threatening) conditions.

There are four primary consequences of acid stopping drugs:

  1. Increased bacterial overgrowth
  2. Impaired nutrient absorption
  3. Decreased resistance to infection
  4. Increased risk of cancer and other diseases

I had originally intended to cover all four of these issues in this article, but as I started to write I realized it would be far too long. So I will cover increased bacterial overgrowth and impaired nutrient absorption in this article, and decreased resistance to infection and increased risk of cancer and other diseases in the next article.

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A Stomach Full of Germs

We’re not going to spend much time on this here since the connection between low stomach acid and bacterial overgrowth was the focus of Part II and Part III.

To review, low stomach acid causes bacterial overgrowth in the stomach and other parts of the intestine. Bacterial overgrowth causes maldigestion of carbohydrates, which in turn produces gas. This gas increases the pressure in the stomach, causing the lower esophageal sphincter (LES) to malfunction. The malfunction of the LES allows acid from the stomach to enter the esophagus, thus producing the symptoms of heartburn and GERD.

Bacterial overgrowth has a number of other undesirable effects, including reducing nutrient absorption, increasing inflammation, and raising the risk of stomach cancer. Studies have confirmed that proton-pump inhibitors (PPIs) can profoundly alter the gastrointestinal bacterial population by suppressing stomach acid. Researchers in Italy detected small bowel bacterial overgrowth (SIBO) in 50% of patients using PPIs, compared to only 6% of healthy control subjects. The prevalence of SIBO increased after one year of treatment with PPIs.

Well-Fed but Undernourished

Stomach acid is a prerequisite to healthy digestion. The breakdown and absorption of nutrients occurs at an optimum rate only within a narrow range of acidity in the stomach. If there isn’t enough acid, the normal chemical reactions required to absorb nutrients is impaired. Over time this can lead to diseases such as anemia, osteoporosis, cardiovascular disease, depression, and more.


Stomach acid plays a key role in the digestion of protein, carbohydrates and fat.

When food is eaten, the secretion of stomach acid (HCL) triggers the production of pepsin. Pepsin is the enzyme required to digest protein. If HCL levels are depressed, so are pepsin levels. As a result, proteins don’t get broken down into their component amino acids and peptides. This can lead to a deficiency of essential amino acids, which in turn may lead to chronic depression, anxiety and insomnia.

At the same time, proteins that escape digestion by pepsin may end up in the bloodstream. Since this is not supposed to happen, the body reacts to these proteins as if they were foreign invaders, causing allergic and autoimmune responses. I’ll discuss this more below.


We can eat the most nutritious diet imaginable, packed with vitamins, minerals and other essential nutrients, but if we aren’t absorbing those nutrients we won’t benefit from them.

As acid declines and the pH of the stomach increases, absorption of nutrients becomes impaired. Decades of research have confirmed that low stomach acid – whether it occurs on its own or as a result of using antacid drugs – reduces absorption of several key nutrients such as iron, B12, folate, calcium and zinc.


Iron deficiency causes chronic anemia, which means that the body’s tissues are literally starving for oxygen.

In one study, 35 of 40 people (80 percent) with chronic iron-deficiency anemia were found to have below normal acid secretion. Iron-deficiency anemia is a well-known consequence of surgical procedures that remove the regions of the stomach where acid is produced.

Researchers have found that inhibition of acid secretion by Tagamet, a popular acid stopping drug, resulted in a significant reduction of iron. At the same time, studies have shown that adding acid has improved iron absorption in patients with achlorydia (no stomach acid production).


Vitamin B12 (cobalamin) is needed for normal nerve activity and brain function. B12 enters the body bound to animal-derived proteins. In order for use to absorb it, the vitamin molecules must first be separated from these proteins with the help of – you guessed it – stomach acid.

If stomach acid is low, B12 can’t be separated from its carrier proteins and thus won’t be absorbed. In one study of 359 people aged 69-79 years with serious atrophic gastritis, a disease characterized by low stomach acid, more than 50 percent had low vitamin B12 levels.

A number of studies have examined the negative effect of PPI therapy on B12 absorption. In a study on healthy subjects treated with 20 mg and 40 mg of Prilosec per day for two weeks, B12 absorption was reduced by 72% and 88% respectively.

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Among other things, folate (folic acid) is vital for keeping the cardiovascular system healthy and for preventing certain birth defects. Low stomach acid levels can interfere with folate absorption by raising the pH in the small intestine. At the same time, when folate is given to achlorydric patients (with no stomach acid) along with an HCL supplement, absorption of the vitamin increases by 54 percent.

Both Tagamet and Zantac reduced folate absorption in another study, though the reduction in the Zantac group was not statistically significant. The overall reduction of folate absorption was sixteen percent. This modest reduction is probably not enough to harm a healthy person consuming adequate levels of folate, but it may cause problems in those with folate deficiency (relatively common) or other health problems.


Calcium makes our bones and teeth strong and is responsible for hundreds, if not thousands, of other functions in our body.

The importance of stomach acid in the absorption of calcium has been known since the 1960s, when one group of researchers noted that some ulcer patients were barely absorbing any calcium at all (just 2 percent). When they investigated they found that these subjects had a high gastric pH (6.5) and very little stomach acid. However, when the researchers gave them HCL supplements, lowering the pH to 1, calcium absorption rose five-fold.


Zinc takes part in several metabolic processes related to keeping cell membranes stable, forming new bone, immune defense, night vision, and tissue growth. In one controlled trial, Tagamet treatment reduced zinc absorption by about 50 percent. Another study found that Pepcid, which raises intragastric pH to over 5, had the same effect.

Although there is little systemic research on the absorption of other nutrients, there is good reason to believe that low acid levels may also effect levels of vitamin A, vitamin E, thiamine (vitamin B1), riboflavin (vitamin B2), and niacin (vitamin B3). Theoretically, the absorption of any nutrient that is bound to protein will be inhibited (PDF).

In Part B of this article I will explain how acid stopping drugs decrease our resistance to infection and increase our risk of stomach cancer and other diseases.

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Join the conversation

  1. I take Pepcid every day as an H2 blocker as well as SIX Zyrtec daily to manage (mostly) my idiopathic angioedema. It makes me nervous to be taking that much, but I was literally starving when it first started and I couldn’t eat at all.
    I was just diagnosed with Hashimoto’s. I’m hoping managing that can help.

  2. One surprising side effect of PPI’s and H2 Blockers that has not been addresed in this article is insomnia. As far as I am aware it is not mentioned on any of the side effect profiles in the leaflets enclosed with the tablets, however I have experienced insomnia after taking both forms of the acid suppression medication, and after attending a nurse lead gastro clinic they did confirm that insomnia has been complained about by other sufferers also.

  3. My gallbladder was removed 23 years ago, and I’ve had reflux pretty much ever since. I’ve had an endoscopy which showed no hiatal hernia and normal acid levels, plus negative H Pylori tests. My gastroenterologist believes I’m actually having bile reflux, amd that there’s no remedy for it. Suggestions?

  4. After of 6 years on nexium, almost 3 weeks ago I stopped cold turkey. The first week was incredible! I thought for sure simply stopping it had cured my excessive belching problem. But after a week reality set in, terrible acid. I felt my stomach filling up with acid all day every day. I got Zantac to take when thinks got bad and I made my diet very strict–bananas, salad with parsley and other non acid veggies–that’s all. Since stopping the nexium I have been very constipated, I use milk of magnesia to relieve that but it causes me terrible acid about 3 hours after I take it. Also, like most things, I can’t take any form of probiotic, it causes terrible acid that will last days before settling down.
    Will I ever get back to normal? Am I just destined to be on a PPI the rest of my life. I really don’t want to start taking it again. I’m always fearful I will get sick and need an antibiotic or fever reducer–which would cause acid so severe is have to go to the ER.
    Please help:(

  5. I have a sphincter valve which is stuck open, so as a result, unknowing of the problem for years, I now have stage2 esophagitis as a result of stomach acid entering my esophagus. I don’t like taking an acid blocker, but what is the alternative? I know all the problems associated with blocking the acid, but with the only alternative is one that leads to cancer of the esophagus, what are my options?

  6. It is very true that many internet sites can not be trust; but is important to be open minded when researching. For those that believe only MD professionals see the following articles by MD and other professionals supporting this article (http://www.everydayhealth.com/digestive-health/experts-are-heartburn-medications-safe.aspx).
    Just recently (3 days), I was for first time visiting a Chiropractor, and she advised me against the use of long term antiacids. She explain that there are a number of research done and to do some research myself. My personal doctor touch the subject lightly in the pass, but did not explain well. I was diagnose with arthritis by a military doctor near 10 years ago and he prescribe Meloxicam for the pains and Omeprazole 20mg to prevent stomach problems. I just stop the Omeprazole and will take it as need it for now as my plan moving forward. The last few years I been prescribe Vitamin D for deficiency, and I wonder if it is due to the antiacid. I have a very good diet that includes fruits, vegetables and various nuts, and spend a good time of the day under the sun. So why would I have vitamin D deficiency?
    By the way, the FDA also agree in the dangers of long term antiacids.

  7. It is very true that many internet sites can not be trust; but is important to be open minded when researching. For those that believe only MD professionals see the following articles by MD and other professionals supporting this article (http://www.everydayhealth.com/digestive-health/experts-are-heartburn-medications-safe.aspx).
    Just recently (3 days) ago I was for first time visiting a Chiropractor, and she advised me against the use of long term antiacids. She explain that there are a number of research done and to do some research myself. My personal doctor touch the subject lightly in the pass, but did not explain well. I was diagnose with arthritis by a military doctor near 10 years ago and he prescribe Meloxicam for the pains and Omeprazole 20mg to prevent stomach problems. I just stop the Omeprazole and will take it as need it for now as my plan moving forward. The last few years I been prescribe Vitamin D for deficiency, and I wonder if it is due to the antiacid. I have a very good diet that includes fruits, vegetables and various nuts, and spend a good time of the day under the sun. So why would I have vitamin D deficiency?
    By the way, the FDA also agree in the dangers of long term antiacids.

  8. I have just weaned myself off PPIs finally after 6-7 yrs. I am 40 years of age. it’s been about 5 weeks since my last tablet. How long would it take for my system to get back to normal and absorbing nutrients properly again. I suffer from anxiety and memory and concentration problems so would like to know how long approx it would take before I notice improvements. Would it be months or closer to a year? I’m trying to have kefir every day and fermented sauerkraut a couple of days a week too to help heal my stomach and acid levels. Any input would be greatly appreciated. Thanks!

    • Hi Louise!
      Well it’s been about 3 months that I quit on my drugs. And step by step my health improves. At first I have had poignant feeling in my mouth, lots of heartburn, etc, but all that is gone now. I suggest that you use apple after every meal, which has to be small, with some vegetables. I have also taken vitamins, because I was out of them since taking PPI-s. Apple worked just great for me and I really appreciate those people here who suggested it to me. In my country we use honey a lot! So if you have a chance, I would also recommend that you drink a water + 1 little spoon of domestic honey. And after 40 minutes you can start your breakfast. Good luck

      • Thank you Lusina! Yes I have used Braggs apple cider vinegar at times and that has helped too. Will try your suggestions. Did you have brain fog too? I worry I am getting early dementia… But I think I could possibly be b12 deficient (which can cause memory issues and poor concentration etc) from taking ppis for extended time

  9. I had my appendix out 2 years ago and have suffered from stomach pain, and a small bowel obstruction ever since. I haven’t been able to tolerate foods like apples, almonds, coconut milk, apple cider vinegar, and the healthy gut-healing bone broth since after the appendectomy. They really tear my stomach apart and the pain feels like a lot of pressure that has sent me to the ER several times. I had an upper endoscopy recently that revealed esophagitis so I’ve been put on a PPI. Why would I not be able to tolerate these healthy foods? I never had a problem consuming them in the past. A low-FODMAP diet seems to help my stomach pain level, but it’s not helping to treat my underlying problem…thank you for your tips! I’ve read that ACV is good for digestion but I cannot handle even a tsp without immense pain.

    • Get checked for h pylori a bacterial infection. My stomach had pain for two years and I ended up in emergency only to find out that my doctor could have found out by a simple blood text. All doctors know about it but will not mention it treatment is antibiotics. Ask for text

  10. If anyone is taking Zantac, can you please comment on whether or not it has depressed your appetite?

  11. Fermented vegetables will solve the whole issue. My friend gave me some kimchi and I had it with dinner. No belching at all that night, and the skin condition I had around my eye, I suspect from a systemic fungal infection caused by too many bouts of antibiotic, (another hellish drug from the pharmaceutical company) also healed that night. So this article is right on, THANKS CHRIS, about the problem being that our good bacteria is destroyed and the remedy is to reseed it with fermented foods.

  12. I am taking Acyclovir, an anti-viral med, Meloxicam, an anti-inflammatory med, and Famotidine (or any H2 Blocker). The H2 Blocker is supposed to keep the first two meds from being absorbed by the stomach–to be passed into the intestine to be absorbed there to work better. So, 1) would that work to make the meds be absorbed in the intestine–and would that do any good., and 2) am I doing any harm by using the H2 Blocker constantly–possibly by not letting food, etc., be absorbed in my intestine?

  13. Hello,
    About 6 months ago my husband rushed me to the hospital because I was in th worst pain I had ever felt (besides childbirth, but on par with it) in my upper abdomen. I was only two weeks post-partum so we had no clue what it could be. After three days in the ER and having had what seemed like every test under the sun they finally did an upper endoscopy and found two large stomach ulcers (not the bleeding type). The GI dr prescribed Protonix but it was giving me stomach cramps and diarrhea so she switched it to rantidine (zantac) 150 mg once daily. After a couple months my heartburn got worse so I’ve been taking it twice daily. Now the past week or so I have been getting very lightheaded and feeling so exhausted! Could this be anemia caused by the antacid? Also, how do i detox from the antacid? Should i stop cold turkey?
    Thank you!!

    • Sorry forgot to mention some things. I am only 21 years old and otherwise very healthy. I do struggle with Candida issues though….Ive been learning recently that candida and gut issues are related. The doctor thought my ulcers had been caused by all the NSAIDS i had been taling in those two weeks after giving birth. I was taking them for uterine cramping and back pain. However i had very severe heartbearn while i was pregnant and was wondering if the ulcers could have already been forming and perhaps the NSAIDS just irritated them?

    • You need to be eraticated from h pylori bacterial infection. Get blood drawn to see if your positive. Ulcers are from h pylori. Eradicate with high doses of anitibitoc the doctor didn’t tell me after two years of horrible pain. Had to find out at the hospital. Better now

  14. My mom has coughed and coughed till she throws up. They thought acid reflux and asthma. Now I cough and cough. When I do people think I am sneezing. I cough till I gag. It’s like I have phlegm in my throat or for no reason I just start coughing. I have been on Prilosec and changed my eating habits. I have been coughing like this for 4 years. Using Prilosec for 2-3 years. I went off Prilosec and ate better for months but still coughed till I gagged. I have been to numerous doctors as well as my mom has. They put a thing down my throat and saw scars on it. I can’t find anyone that knows that this is and I don’t want to live with this contstant cough for another 20 years. Any one else with this problem. My mom also has bone issues and I have heard Prilosec isn’t good for bones.

    • Your coughing is more than likely caused by something you’re eating. I start to cough and produce phlegm anytime I eat dairy or gluten containing products.

      • Same here. If I eat dairy or grain I cough and cough and clear my throat over and over. So annoying. Also, grain makes my heart race. Weird, huh?

    • Hi, I’m most definitely not a doctor but have experienced the phlegm and use omeprazol every day, but have heard from doctors about what all causes the phlegm. Things like milk, meats and sinus, so I guess you could check out that and see if diminished phlegm helps at all.

    • Have your pancreas checked out… It may be connected… I had all the same problems plus… Throwing up for no reason and fast… They found a Non cancerous tumor in the middle of my pancreas purely by the Symtom and pain… They found it by mistake… It’s just a simple sonagram or MRI… Check it out‼️

      • I never go to doctors except for my annual check up which is free because I have medicare. Otherwise, I’d never go. Everything they prescribe has a negative side effect to it. From all the health practitioners that I do respect, I read that fermented foods help digest your food and balances your gut flora. I use to make homemade sauerkraut and never had this acid reflux problem, but an herbalist told me that fermented foods have nitrates in it, even the homemade ones, using only regular salt turns into nitrates, so I stopped eating them. Then I met a Korean woman who gave me some homemade kimchi. I noticed that she was very energetic and alert, so nitrates or not, I ate the kimchi and had no belching at all through the night and I slept a full 8 hours without needing to get up to pee. Thank you for the suggestion, but I definitely would not go to a doctor looking for a possible problem, especially cancer if I have no symptoms.

    • If you take any drugs for high blood pressure, they can be causing the cough -Seriously!
      I had a cough like that many years ago when exposed to buckwheat flour (worked in a pancake house) and it nearly killed me. I would cough and cough until vomiting. My weight dropped to 85 lbs. I went to military doctors 9 times!! All they did was prescribe cough medicine. I was incredibly weak. Finally went to a private doctor. I had to quit my job and was prescribed strong antihistamines and rest. The cough stopped immediately and I slowly regained strength and weight. Here it is 45 years later and I have a severe gluten and wheat allergy, and am lactose intolerant, but no cough. It’s either blood pressure meds or you are allergic to something. Check it out.

    • I coughed for years untill i started taking zertec d they told me had acid reflux cough now i cough a little but nothing like the years of gagging and coughing

    • This sounds very much like a parasite issue. Parasites can actually affect the lungs, and frequently one family member can infect another. Most mainstream doctors do not even test for this, so I would suggest you ask for testing or begin researching at huldaclark.com and various Facebook groups with knowledgeable admins. Good luck.

    • Coughing can also be bronchiestasis. I was just diagnosed. It can be caused by GERD.