If you’ve ever experienced acid reflux, you’ve likely taken an antacid. These medications neutralise the acid made by your stomach, providing immediate relief from heartburn. You can purchase antacids over the counter. However, these acid neutralisers don’t treat the underlying causes of heartburn or indigestion.
Antacids are not to be confused with other acid neutralisers. Antacids don’t alter the production of acid, like H2 receptor blockers or proton pump inhibitors (PPIs). Instead, they lower the volume of acid in the stomach or oesophagus at that particular time.
In this guide:
- What are Antacids?
- Types of Antacids
- When Can You Take Antacids?
- Who Can Take Antacids?
- Acid Reflux Treatments
What are Antacids?
Antacids are a medication used to provide immediate relief from heartburn and indigestion. Your stomach produces acid to break down food and kill off pathogens.
In some people, however, acid can flow back up the food pipe, leading to acid reflux. This is often characterised as heartburn, where the acid irritates or inflames the oesophagus. Excess acid production is linked to smoking, eating fatty foods, and certain medical conditions.
You might notice these symptoms:
- A burning sensation in your chest or stomach
- An acidic taste in your mouth
- Feeling indigested or bloated
- Coughing or hoarseness
Antacids neutralise the acid via a simple chemical reaction. Acidity refers to the concentration of hydrogen ions. The more hydrogen ions there are, the more acidic something is. A common antacid is calcium carbonate. It reacts with acid to produce water, a salt, and carbon dioxide. That’s why you burp after taking an antacid.
Here’s a simple equation:
CaCO 3 + 2HCl → CaCl2 + H2 O + CO2
Your stomach acid (hydrochloric acid) is neutralised in this reaction, providing immediate relief from your discomfort.
Types of Antacids
Several types of antacids are available. The most common include:
Calcium Carbonate a common antacid and provides quick relief from acid reflux and heartburn. It’s the main ingredient in Tums and Rolaids.
Magnesium hydroxide offers fast relief from symptoms but can cause diarrhoea. It’s often combined with aluminium hydroxide to balance its effects. It’s found in Milk of Magnesia.
Aluminium Hydroxide reduces stomach acid but is linked to constipation. It’s found in Alternagel and Alu-Cap.
Sodium Bicarbonate neutralises stomach acid but causes belching and gas due to CO2 release. Alka-Seltzer contains sodium bicarbonate.
Hydrotalcite is less common than other types of antacids.
Bismuth Subsalicylate has antacid properties, although it’s primarily used for nausea and diarrhoea. Pepto-Bismol is the most famous example.
When Can You Take Antacids?
Antacids are primarily used to treat heartburn and indigestion. The specific conditions antacids treat include:
Acid reflux or gastroesophageal reflux disease (GORD) is a condition where acid from the stomach backflows into the oesophagus, causing irritation and inflammation.
Gastritis refers to the inflammation of the stomach lining. The high concentrations of acid can exacerbate the condition.
Stomach ulcers are openings in the stomach lining. Acid can exacerbate and irritate ulcers, prolonging the condition.
Antacids are temporary, symptomatic treatment. You should never take antacids for prolonged periods of time or in large quantities.
Who Can Take Antacids?
Most individuals can use antacids without any issues. However, it’s important to consult your healthcare provider before starting antacids if you:
- Are on a low-sodium diet
- Are pregnant or trying to become pregnant
- Are taking other medications
- Are under the age of 12
- Have heart failure
- Have high blood pressure
- Have liver or kidney disease
It’s easy to consider antacids a minor treatment. In part, that’s true. However, as they neutralise the current hydrogen ions in the stomach, the body is forced to pump more to restore the pH. Continually consuming antacids in large quantities can, therefore, cause significant problems for some individuals.
Antacid Side Effects
Complications due to antacids are generally rare. These medications are well-tolerated. Young infants and older adults are most affected. Side effects include:
- Constipation or diarrhoea
- Headache
- Nausea and vomiting
- Gas and belching
- Stomach cramps
If taken in large quantities, certain types of antacids can cause changes in your blood chemistry. For example, excessive consumption of antacids that neutralize stomach acid can lead to an increase in blood bicarbonate levels, resulting in metabolic alkalosis, where the blood becomes too alkaline. The body closely monitors blood pH levels to regulate breathing rate. An elevated blood pH can slow down your breathing, particularly if you have pre-existing metabolic conditions.
Other severe complications include microcytic anaemia, weakened bones, and excess calcium levels in the blood (hypercalcaemia).
Acid Reflux Treatments
Antacids are a temporary treatment designed to provide immediate symptomatic relief. If you’re continually experiencing acid reflux, you might consider the following treatments:
H2 Blockers: These medications reduce stomach acid production by blocking histamine receptors on acid-producing cells in the stomach. They are effective for treating heartburn and other symptoms associated with acid reflux, providing relief that lasts up to 12 hours.
Proton Pump Inhibitors (PPIs): PPIs work by directly inhibiting the enzyme system responsible for acid secretion in the stomach, offering a more profound and longer-lasting reduction in stomach acid than H2 blockers. They are commonly prescribed for persistent acid reflux conditions and are especially effective in healing erosive esophagitis.
Your doctor can prescribe higher-strength versions of these medications. If you’re continuing to experience symptoms despite medication, then surgery may be advised. This involves tightening the lower oesophageal sphincter, which forms a barrier between the stomach and the oesophagus.
Diagnosing acid reflux disease is crucial to evaluating your treatment. If you continually require antacids to treat acid reflux, you may need reflux testing.
A gastric reflux test involves inserting a pH monitor into the oesophagus for 24 hours. It can detect the presence of acid, confirming if you have GORD. It’s the gold standard for reflux testing. Learn more at our 24-hour acid reflux testing page for further details.
Recent studies have shown a possible connection between GERD and Heart Disease. While the exact mechanisms are still under investigation, some theories suggest that chronic inflammation caused by GERD may contribute to the development of heart disease.