Are H2 Blockers the Solution for GERD and Stomach Acid Production?

H2 blockers and proton pump inhibitors are GERD medications which decrease the amount of stomach acid produced and released. As mentioned on my other pages on this subject, conventional help for GERD focuses on control of stomach acid.

Drugs in the H2 category, such as Zantac (Ranitidine HCl), Tagamet (cimetidine), Axid (nizatidine) and Pepcid (famotidine), work by stopping the production of histamine. 

They are also called histamine type-2 receptor antagonists (H2RAs). These medications can provide relief in 30 minutes and last up to 12 hours in some cases.

You Think All Histamine is Bad?

You probably have heard about antihistamines like Benadryl to combat allergic reactions and wonder how histamine can be involved in GERD.  Allergic reactions are not the only use of histamine.

Depending on the receptor, H1 through H4, histamine can bind to on different cells and thus have desirable and undesirable consequences. A few other examples where histamine may be involved are in:

  • Bronchial-tube constriction
  • Vasodilation (widening of blood vessels)
  • Motion sickness
  • Sleep regulation (which is why some antihistamines cause drowsiness)
  • Neurotransmitter function
  • Signaling white blood cells to the scene of an infection
  • Stomach acid secretion (a receptor 2 interaction, thus the name “H2 blocker.”)

In the stomach, histamine stimulates acid-producing cells to produce stomach acid. 

What are the Side Effects of Histamine-2 Blockers?

H2 blockers are meant to be used short-term (less than 2 weeks) unless prescribed by a physician. Minor side effects according to www.medicinenet.com and other sources include:

  • Constipation
  • Diarrhea
  • Fatigue
  • Headache
  • Dizziness
  • Runny or stuffy nose
  • Sore throat
  • Cough
  • Insomnia
  • Muscle pain
  • Nausea
  • Vomiting
  • Erectile dysfunction.

Although rare, major side effects include: agitation, anemia, confusion, depression, easy bruising or bleeding, hallucinations, hair loss, irregular heartbeat, rash, visual changes, and yellowing of the skin or eyes.

They also interfere with the body’s ability to use drugs that require acid for proper absorption, and they can interfere with absorption and/or excretion of nutrients like chromium.

One thing that is lesser known is that H2 Blockers are shown to disrupt gut microbiota. A 2013 study in premature infants showed that microbial diversity was lower and relative abundance of Proteobacteria (a phylum comprised of many Gram-negative pathogens) was increased in the stools of infants receiving H2-blockers compared with those who had never received them. The authors of the study suggested that the use of H2 blockers in premature infants may predispose the vulnerable immature gut to necrotizing enterocolitis, a very serious and dangerous infection of the intestines.

What are 3 Common H2 Blockers and Their Ingredients?

Let’s look at ingredients in these three histamine-2 blockers. Always read the product information sheets! At the time of this writing:

Zantac – Comes in 3 varieties with strengths of 75 mg or 150 mg rantidine per tablet to be swallowed. Some questionable ingredients may be a synthetic red iron oxide, triacetin [a chemical commonly used as a cosmetic biocide (literally means life-killer!) plasticizer and solvent in cosmetics (makeup, etc.)], artificial color, artificial sweetener, and synthetic preservative.

In April of 2020, the US FDA issued an alert requesting manufacturers to withdraw all prescription and over-the-counter (OTC) ranitidine drugs from the market immediately. Ranitidine products like Zantac contain a contaminant known as N-Nitrosodimethylamine (NDMA) that is a probable human carcinogen (a substance that could cause cancer). The FDA determined that the impurity of NDMA in some ranitidine products increases over time and when stored at higher than room temperatures may result in consumer exposure to unacceptable levels of this impurity. As a result of this immediate market withdrawal request, ranitidine products will not be available for new or existing prescriptions or OTC use in the U.S.

Consumers were advised to stop taking any ranitidine tablets or liquid they currently have, dispose of them properly and not buy more. For people who wanted to continue to use medications in the place of ranitidine,  they should consider using other approved OTC products.

Patients taking prescription ranitidine were advised to speak with their health care professional about other treatment options before stopping the medicine. There are multiple drugs approved for the same or similar uses as ranitidine that do not carry the same risks from NDMA. As of April, 2020,  the FDA’s testing has not found NDMA in famotidine (Pepcid), cimetidine (Tagamet), esomeprazole (Nexium), lansoprazole (Prevacid) or omeprazole (Prilosec).

Tagamet HB 200 – Questionable ingredients are cornstarch (probably GMO), preservative, sodium lauryl sulfate. As Snopes.com says regarding sodium lauryl sulfate in personal care products, it “is an irritant…and you really don’t want to swallow the stuff.”

Pepcid – Comes in 3 product varieties: 2 are Pepcid AC in tablet form with just famotidine as the active ingredient with starch (GMO?) and talc as the main questionable ingredients; and 1 is Pepcid Complete with the antacids calcium carbonate and magnesium hydroxide and the H2 blocker famotidine as the active ingredients with cornstarch (probably GMO), corn syrup solids, dextrose, artificial colors and flavors, maltodextrin, mineral oil, artificial sweeteners and triacetin (see Zantac, above) as possible inactive ingredients.

Note that each flavor of Pepcid Complete contains lactose as an inactive ingredient.

Are H2 Blockers the Solution for GERD?

You can see that histamine-2 blockers are not the answer for a cure for GERD, since they are meant to be used for less 2 weeks and they have some undesirable side effects and ingredients. Instead, see which diet and lifestyle changes you can make to try to eliminate the cause of frequent reflux and heartburn.

Check out these other pages:

Treatment for GERD with antacids

Treatment for GERD with proton pump inhibitors

Help for GERD with probiotics.

Return to the page about GERD causes.

Return to the page about GERD symptoms, diagnosis and complications.


Return to the Homepage.

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