Antacids are a medicine used to treat heartburn and indigestion. You can get antacids over-the-counter without a prescription. Antacids work quickly to reduce the amount of acid in your stomach to relieve symptoms. Antacids don’t treat the underlying causes of heartburn and indigestion.


What are antacids and what does an antacid do?

Antacids are a medicine that relieves heartburn and indigestion by reducing the amount of acid in your stomach. Antacids neutralize the acid in your stomach by stopping an enzyme that creates acid to break down food for digestion (pepsin).

You can purchase antacids over-the-counter without a prescription.

There are two types of antacids: liquid and chewable tablets.


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What symptoms does an antacid relieve?

Antacids relieve symptoms that cause heartburn and indigestion including:

What are common brand names of antacids?

Popular brand names for antacids include:

  • Tums ®.
  • Mylanta ®.
  • Pepto-Bismol ®.
  • Rolaids ®.


What are antacids approved for?

The Food and Drug Administration approved antacids for treating mild cases of heartburn and indigestion. A mild case refers to heartburn that happens occasionally or every once in a while rather than every day.

Antacids also help combat symptoms of:

  • Acid reflux (GERD or gastroesophageal reflux disease).
  • Stomach lining inflammation (gastritis).
  • Stomach ulcers.

Antacids work quickly to relieve symptoms for a few hours. Antacids don't treat underlying medical conditions that cause symptoms.

Who can take antacids?

Most people can take an antacid safely. Ask your healthcare provider if it's safe to start taking antacids if you:


Additional Common Questions

What forms do antacids come in?

Antacids come in two forms:

  • Liquid.
  • Chewable tablet.

Liquid antacid works more quickly than chewable tablets to alleviate symptoms of heartburn and indigestion.

What dosage strengths do antacids come in?

The dosage for antacids vary and is dependent on your age and reason for use. Dosing also varies by manufacturer. Be sure to follow the instructions outlined on the packaging.

What ingredients are in antacids?

The active ingredients in antacids can vary depending on the type and brand. Some common ingredients are aluminum, calcium, magnesium and salts (sodium), specifically:

  • Alginate.
  • Aluminum hydroxide.
  • Calcium carbonate.
  • Magnesium carbonate.
  • Magnesium hydroxide.
  • Magnesium trisilicate.
  • Sodium bicarbonate.

How should I take an antacid?

You should take antacids when you have symptoms of heartburn or indigestion. You can also take an antacid one hour after eating, which is when you might experience symptoms of heartburn.

Always follow instructions on how much and how frequently you should take antacids according to the label of each antacid brand, since they may vary.

If you experience symptoms at night and take an antacid before bed, don’t eat food with an antacid at that time.

If you take antacids regularly, contact your healthcare provider about your symptoms to examine any underlying causes of frequent heartburn.

What are the side effects of an antacid?

Complications after taking an antacid mostly affect infants or people over the age of 65. Side effects could include:

  • Constipation or diarrhea.
  • Gas (flatulence).
  • Headache.
  • Nausea and vomiting.
  • Stomach cramps or pain in the abdomen.

Serious side effects could include:

  • Acid rebound: Antacids cause your body to produce more acid, which worsens symptoms.
  • Neurotoxicity: An antacid changes the function of your nervous system.
  • Microcytic anemia: Iron deficiency.
  • Osteopenia: Weakened bones.
  • Hypercalcemia: Too much calcium in your blood.

Don't take antacids frequently. If you experience symptoms of heartburn or indigestion daily, reach out to your healthcare provider to look into the cause of your symptoms.

Are there any serious interactions with antacids?

Antacids can interact with how other medicines absorb into your body. Before taking antacids, contact your healthcare provider to see if it is right for you. You should take other medicines one hour before or at least four hours after taking an antacid to prevent interactions.

Can I drink alcohol with antacids?

Yes, you can drink alcohol and take an antacid, but alcohol might make your symptoms worse and further irritate your stomach.

What should I tell my healthcare provider before starting antacids?

If you plan on taking antacids to treat heartburn and indigestion, talk with your healthcare provider about your symptoms and how often you have symptoms. Your provider might offer tests to further diagnose what is causing your discomfort and will decide whether or not you have an underlying condition.

Can I take an antacid if I’m pregnant or thinking of becoming pregnant?

It’s usually safe to take antacids if you are pregnant or thinking about becoming pregnant. But, you should always check with your healthcare provider first. It is also important to check the ingredients in the antacid you plan on taking. Ingredients like aluminum salts and calcium are safe to consume if you are pregnant but don’t take more than the daily recommended dosage.

Do antacids pass into breast milk?

Some ingredients, like calcium, that are found in antacids can pass into breastmilk. It is safe to take antacids if you are breastfeeding (chestfeeding) as long as you don’t exceed the daily recommended dosage for antacids.

Are antacids addictive?

No, antacids aren’t addictive. If you’re taking antacids regularly to treat your symptoms, talk with your healthcare provider. Antacids aren’t a cure for any underlying conditions that cause your symptoms.

What should I do if I miss a dose of antacid?

You should only take antacids to treat symptoms at the frequency identified on the label of the medicine. If you miss a dose, don’t panic. You can take an antacid at any time as long as it doesn’t interfere with any other medicines you are currently taking.

What medicines are commonly mistaken as antacids?

Several types of medicines treat heartburn or indigestion but are not antacids because the ingredients work in different ways than those of antacids. Common medicines that are not antacids include:

  • Esomeprazole (Nexium ®): Treats acid reflux and ulcers.
  • Famotidine (Pepcid ®): Treats stomach ulcers, esophagitis, GERD.
  • Omeprazole (Prilosec ®): Treats stomach and esophagus problems.
  • Pantoprazole (Protonix ®): Treats stomach and esophagus problems and GERD.
  • Simethicone (Gas-X ®): Treats gas and bloating.

A note from Cleveland Clinic

Antacids are a great source of relief from symptoms of heartburn and indigestion, especially if you just ate hot wings or spicy food. Always follow dosage instructions on the label and talk with your healthcare provider before taking antacids to see if they will interfere with any medicines that you’re currently taking.

Medically Reviewed

Last reviewed on 05/20/2022.

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