Antacid medications

What are antacids used for?

Antacids and acid-suppressing medications are used in the treatment of heartburn associated with gastro-esophageal reflux disease (GERD). The medical term for heartburn is esophagitis, which means inflammation of the esophagus. 

Most antacids and acid-suppressing medications do nothing to prevent the regurgitation of stomach contents back into the esophagus; rather the purpose of these medications is to neutralize or restrict the production of stomach acid, and thereby allow the esophagus to heal.

How antacids work

Different medications work in different ways. Some have a single action; others have a combined action. Antacids and acid-suppressing medications achieve one or more of the following:

     * Provide a barrier to restrict the back flow of stomach contents into the esophagus.

     * Neutralize stomach acid.

     * Restrict the production of stomach acid.

There are numerous antacids and acid-suppressing medications on the market. Many are available over-the-counter. Most are not suitable to be given to babies. Below describes the action of medications commonly prescribed for babies in the treatment of esophagitis.


Antacids (e.g. Maalox®, Mylanta®) neutralize stomach acid. These include a metal ion, such as aluminium, magnesium, calcium or sodium, which is linked to an alkali, such as hydroxide, carbonate, bicarbonate or trisilicate. The metal ion determines how quickly the antacid will work (as well as likely side effects) and the alkali determines how long it will be effective for. Most antacids are made up of a mixture of different ingredients, which aim to provide rapid but sustained relief.

Some antacids, e.g. Infant Gaviscon®, contain alginic acid, a gum that floats on the surface of stomach contents. The purpose of alginic acid is to provide a barrier to stop gastric fluids from being refluxed back into the esophagus. A fully upright position needs to be maintained to achieve this benefit. Lying down, as babies often do, decreases the effect of alginic acid. 

Once popular medications in the treatment of suspected esophagitis, antacids are seldom recommended for babies these days because of their high sodium and aluminium content.

Acid-suppressing medications

Ranitidine (Zantac®) works by restricting production of stomach acid. Ranitidine is a histamine H2-receptor antagonist. Basically this means it blocks histamine. It works on a pump in the stomach that releases acid when stimulated by histamine. By preventing histamine from stimulating this pump, Ranitidine will significantly reduce the amount of acid that is released into the stomach. Ranitidine is only available by doctor\'s prescription.

Omeprazole (Prilosec®, Losec®) also restricts the production of stomach acid but in a different way. Omeprazole is a proton pump inhibitor (PPI). It decreases the amount of acid in the stomach by binding to the gastric pump and blocking the secretion of acid into the stomach. PPI are the most powerful of all acid-suppressing medications currently available. Omeprazole is only available by doctor\'s prescription.

Lansoprazole (Prevacid®, Zoton®) is also a PPI that works in a very similar way to Omeprazole. Lansoprazole is only available by doctor\'s prescription.

Special considerations

  1. Any medications that come in tablet form have not been developed for babies.
  2. Antacids with high levels of calcium carbonate should never be given to babies.
  3. Antacids containing sodium bicarbonate should never be given to babies.
  4. Infant Gaviscon® should not be given to a pre-mature baby; a baby suffering from fever, vomiting, diarrhea, or dehydration. 
  5. Infant Gaviscon® in combination with soy infant formula can cause severe constipation.
  6. Over-the-counter antacid medications should not be given to babies without medical advice
  7. Do not give a baby home or natural remedies to treat acid reflux without first discussing this with a medical doctor, as some remedies can cause serious harm to babies. 

Side effects

Most side effects directly related to antacids and acid-supressing medications are generally mild and tend to pass by themselves. More serious side effects are rare but can occur, so it\'s important to be aware what these are. [Read the leaflet that comes with the medication for a full list of potential side effects.]

Medications containing alginic acid: (Infant Gaviscon®) Constipation, diarrhoea.

Antacids containing aluminium: (Maalox®, Mylanta®) Constipation, abdominal discomfort, loss of appetite, mood or mental changes, weakness, swelling of wrist or ankles, bone pain.

Antacids containing magnesium: Diarrhea, dizziness, loss of appetite, problems in urination (difficult, pain), irregular heartbeat, abdominal discomfort, mood or mental changes, weakness and tiredness.

Antacids containing sodium bicarbonate: Nausea and vomiting, slow breathing, problems urinating (frequent urge), headaches, loss of appetite, mood or mental changes (feeling nervous or restless), muscles pain, tiredness and weakness.

Medications such as Ranitidine, Omeprazole or Lansoprazole: (Zantac®, Prilosec®, Losec®, Prevacid®, Zoton®) Headache, diarrhea, constipation, upset stomach, vomiting, stomach pain, cough, dizziness or mild rash.

Secondary adverse effects

Antacids and other acid-suppressing medications are so frequently prescribed for babies suspected of suffering from acid reflux in Western societies that many people consider them harmless. This is not correct! Any medication has the potential to cause unwanted consequences. In some cases, medications can create greater problems for a child or adult than the condition they were given to treat. While the side effects directly linked to these medications are generally mild, the secondary adverse effects associated with neutralizing or restricting the production or release of stomach acid has the potential to be far more troublesome. 

Stomach acid is not a mistake of nature. Stomach acid plays a vital role in many digestive and immune processes, a few of which include:

  1. Partial digestion (break down) of proteins in the stomach;
  2. Kill germs that enter the body in food and drink;
  3. Support the growth of friendly bacteria in the intestinal tract;
  4. Aid the absorption of vitamins and minerals.

Altering the body\'s natural chemical balance by lowering stomach acid can have negative consequences! When stomach acid production is low this can cause dysfunction throughout the entire digestive system and beyond. What parents and their baby\'s doctor need to decide is if the benefits of giving a baby these medications outweighs the potential risk of secondary adverse effects. 

The following are problems experienced by adults taking antacids and/or acid-suppressing medications. [It is unethical to undertake clinical drug trials on babies, so we can only guess at what the implications might be based on adult studies.]

Rebound acidity [Source] 

The subconscious brain is able to sense when stomach acid production is low, and will attempt to compensate by releasing a hormone that stimulates the growth of acid producing cells in the stomach. Consequently, the number of acid producing cells increase. [This is why people who regularly take acid-suppressing medications sometimes find they need to increase their dosage.] If the medication is ceased abruptly this may then enable the release of acid beyond what is needed. The release of excess stomach acid could make the symptoms of acid reflux worse compared to prior to the commencement of treatment. Rebound acidity can cause a vicious cycle of dependence on acid-suppressing medications.

Rebound acidity associated with long-term use of acid-suppressing medications can cause people to suffer from acid reflux even in cases where they did not previously suffer from it. One study found that after 8 weeks of using PPI’s, participants who had no prior history of acid reflux developed this problem owing to rebound acidity. [Source

In the cases of babies who have been misdiagnosed with acid reflux, the good news is that their little bodies are able to return to normal acid production within a week or two after medications are ceased. 

Vitamin and mineral deficiency

Stomach acid aids the absorption of vitamins and minerals, such as calcium, magnesium, iron, zinc, copper, chromium, selenium, manganese, vanadium, molybdenum, cobalt, Vitamin B12, Vitamin D, folic acid, ascorbic acid, and beta-carotene.

Vitamin and mineral deficiencies can occur as a result of low stomach acid, and this can lead to problems such as iron deficiency anemia, pernicious anaemia and rickets among other problems. [Source] Anemia, in turn linked to poor growth and increased risk of infections among other problems. Rickets causes pain and deformity of bones. 

Gastro-intestinal infections [Source]

Stomach acid is the body\'s first line of defense against harmful microorganisms (bacteria, viruses, fungal spores and parasites) that enter the body in food, water and other fluids, including infant formula.

Babies are especially vulnerable to infective illnesses because their immune system is immature. A healthy immune system relies heavily on healthy intestinal micro-flora.

Intestinal dysbiosis

Stomach acid supports the growth of friendly bacteria in the intestinal tract. Friendly bacteria provide many health benefits such as: the synthesis of vitamin K and group B vitamins; aid the digestion of lactose; keep the lining of the intestinal wall healthy; and keep pathogens (harmful microorganisms) in check, preventing them from multiplying to unhealthy levels. [Source

Pathogens flourish in an environment where acid levels are low. Intestinal dysbiosis is a condition when there are insufficient numbers of friendly bacteria to prevent intestinal pathogens from causing harm. Intestinal pathogens cause gastro-intestinal infections and disrupt normal digestive processes, which can be mistakenly attributed to food intolerance.

It can take from one to a number of months for a baby’s intestinal micro-flora to establish. The type of food and medications given to a baby in the early weeks and months will influence the type of micro-flora that colonise in his/her intestinal tract. Breast-milk supports the growth of friendly bacteria better than infant formula. By lowing stomach acid, antacids and acid-suppressing will result in decreased numbers of friendly bacteria and increased numbers of harmful microorganisms in the intestinal tract of both breast and formula fed babies.  

Food allergies 

Low stomach acid has been linked to increased incidence of food allergies in adults. [Source] A major function of stomach acid is to initiate the digestion of protein molecules. Chemically neutralising or blocking stomach acid with medications may make harmless food proteins into potential allergens if they are able to gain entry into the blood stream through lining of the intestinal wall.  

Babies under the age of six months are especially vulnerable to developing food allergies for a number of reasons. One reason is because they have a ‘leaky gut’. This means the lining in their small intestines has naturally occurring small openings. These close between the ages of four to six months. These openings increase the risk of large molecules of incompletely digested protein gaining entry into a baby\'s bloodstream and thereby triggering an allergic reaction.

Urinary Tract Infections [Source] 

Just how low stomach acid is linked to an increased incidence of kidney infection is not fully understood at present, but it is thought to be related to impaired immune function that may occur in response to altering the micro-flora in the intestinal tract.

Babies have an immature immune system. They are also at increased risk of developing urinary tract infections owing to wearing diapers. Diapers will at times become contaminated by fecal matter (poop), and while baby is wearing one, it will provide a warm, moist environment for pathogens to flourish.

Pneumonia [Source]

Low stomach acid is linked to an increased risk of pneumonia. It’s thought that pathogens, refluxed in gastric juices from the stomach, may enter the trachea (windpipe) and upper airways causing a respiratory infection. Given that bacteria and other pathogens thrive in an environment where acid levels are lower than normal, acid reducing medications could clearly play a role in such infections. 

The Pediatric GERD Clinical Practice Guidelines cites several safety concerns regarding the use of antacids and acid-suppressing medications by babies, including known adverse effects. 

Acid reflux drugs: Call for FDA to have stricter warnings

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Added April 2004. Revised 2008; Jan 2014.