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Your doctor may recommend an antacid. These are available over the counter. Antacids are best for rapid relief of occasional GERD symptoms, mainly heartburn. For the best symptom relief, you should take antacids immediately after eating and within 1 to 3 hours of bedtime. There are many types of antacids available, and your doctor or pharmacist can help you choose one that is right for you.

How Antacids Work

Antacids work by neutralizing the acid in your stomach. They also make reflux less acidic, causing less damage to your esophagus. Antacids may also increase lower esophageal sphincter pressure, causing less reflux.

Possible Side Effects of Antacids

Each type of antacid can cause different side effects. You should speak with your doctor if you have any of the following, especially if they bother you.

  • Calcium carbonate can cause constipation. If used in very high doses, it can also cause a condition in which the medication no longer reduces acid reflux but instead actually causes it. This is called rebound hyperacidity.
  • Sodium bicarbonate can cause imbalances in the electrolytes, or salts, in your blood, changing its chemistry.
  • Magnesium hydroxide and magnesium oxide can affect bowel function, sometimes causing diarrhea. Because it can build up in the kidneys, don't take it if you have kidney problems.
  • Aluminum hydroxide can cause constipation. Because it can build up in the kidneys, don't take it if you have kidney problems. Also, aluminum hydroxide antacids may reduce substances in your blood required for energy, called phosphates.

Possible Drug Interactions with Antacids

To help you avoid unnecessary side effects, use caution when taking antacids with other drugs. Antacids can reduce the absorption of different medications. Tell your doctor about all other drugs you are taking - it's a good idea to let your doctor see your other prescription containers.

Drugs to Avoid with Antacids

Before you start taking an antacid, tell your doctor if you take any of the following:

  • amphetamines
  • antibiotics
  • anti-inflammatory drugs
  • arrhythmia drugs
  • arthritis drugs
  • asthma drugs
  • blood pressure drugs
  • blood thinners
  • diabetes drugs
  • drugs for gout
  • drugs for mental illness
  • drugs for Parkinson's disease
  • drugs for tuberculosis
  • heart drugs
  • seizure drugs
  • thyroid drugs
  • ulcer drugs