In April 2020, the Food and Drug Administration (FDA) requested that all forms of prescription and over-the-counter (OTC) ranitidine (Zantac) be removed from the U.S. market. This recommendation was made because unacceptable levels of NDMA, a probable carcinogen (cancer-causing chemical), were found in some ranitidine products. If you’re prescribed ranitidine, talk with your doctor about safe alternative options before stopping the drug. If you’re taking OTC ranitidine, stop taking the drug and talk with your healthcare provider about alternative options. Instead of taking unused ranitidine products to a drug take-back site, dispose of them according to the product’s instructions or by following the FDA’s guidance.

Ranitidine, brand name Zantac, is now marketed as Zantac 360, which contains a different active ingredient (famotidine). Famotidine is in the same class as ranitidine and works the same way but has not been found to contain unacceptable levels of NDMA.

H2 receptor blockers are a class of medications that can be used to treat conditions that cause excess stomach acid. These medications are available over the counter and by prescription. Common H2 receptor blockers include:

  • nizatidine (Axid)
  • famotidine (Pepcid, Pepcid AC)
  • cimetidine (Tagamet, Tagamet HB)

H2 receptor blockers are most commonly used to treat gastritis, or inflamed stomach, and to treat peptic ulcers. Peptic ulcers are painful sores that form in the lining of the stomach, lower esophagus, or duodenum, which is the first part of the small intestine. They often develop as a result of inflammation and excess stomach acid. Doctors may also recommend H2 receptor blockers to keep peptic ulcers from returning.

H2 receptor blockers are also frequently used to relieve the symptoms of gastroesophageal reflux disease (GERD). GERD is a chronic form of acid reflux, which causes acidic stomach contents to flow back up into the esophagus. The frequent exposure to stomach acid can irritate the esophagus and lead to uncomfortable symptoms, such as heartburn, nausea, or trouble swallowing.

H2 blockers may also be used to treat less common conditions such as Zollinger-Ellison syndrome, a condition that causes an increased production of stomach acid

Doctors may also recommend H2 receptor blockers for off-label use. This means using the medicine to treat a condition that the medication hasn’t been approved to treat. For example, H2 receptor blockers might be used to treat pancreatic problems or used in cases of allergic reaction, even though they aren’t traditionally used for these purposes.

When you take an H2 receptor blocker, the active ingredients travel to specific receptors on the surface of the stomach cells that release acids. The medication inhibits certain chemical reactions in these cells so that they aren’t able to produce as much acid. According to the National Institutes of Health, H2 receptor blockers decrease stomach acid secretions over a 24-hour period by 70 percent. By reducing the amount of acid in the stomach, any damaged tissues are allowed time to heal.

Most of the side effects associated with H2 receptor blockers are mild and usually subside as a person takes the medication over time. Only 1.5 percent of people stop taking H2 receptor blockers due to the side effects.

Some of the side effects that may occur with H2 receptor blockers include:

  • constipation
  • diarrhea
  • difficulty sleeping
  • dry mouth
  • dry skin
  • headaches
  • ringing in the ears
  • a runny nose
  • trouble urinating

Call your doctor if you have any other symptoms that you suspect may be due to taking an H2 receptor blocker.

In rare cases, H2 receptor blockers might cause more serious side effects, such as:

  • blistered, burning, or scaling skin
  • changes in vision
  • confusion
  • agitation
  • difficulty breathing
  • wheezing
  • chest tightness
  • irregular heartbeat
  • hallucinations
  • suicidal thoughts

Call your doctor or go to the hospital right away if you experience any of these symptoms.

Despite their potential side effects, H2 receptor blockers are usually a very effective treatment for conditions that cause excess stomach acid. You and your doctor can discuss the potential risks and determine whether H2 receptor blockers are the best option for your particular condition. You should never stop taking your medication without talking to your doctor about it first.

Proton pump inhibitors (PPIs) are another type of medication used to reduce stomach acid and treat acid reflux or GERD. Examples of PPIs include esomeprazole (Nexium) and pantoprazole (Protonix).

Both medications work by blocking and decreasing the production of stomach acid, but PPIs are considered stronger and faster in reducing stomach acids. However, H2 receptor blockers specifically decrease the acid released in the evening, which is a common contributor to peptic ulcers. This is why H2 receptor blockers are specifically prescribed to people who have ulcers or who are at risk for getting them. PPIs are more often prescribed for people who have GERD or acid reflux.

Doctors usually don’t recommend taking both a PPI and an H2 receptor blocker at the same time. H2 receptor blockers can interfere with the effectiveness of PPIs. If your GERD symptoms don’t improve with the use of a PPI, your doctor may recommend an H2 receptor blocker instead.

If you have peptic ulcers or GERD, your doctor will likely recommend that you avoid taking specific medicines and that you make certain lifestyle changes to ease your symptoms.

If you have peptic ulcers, your doctor may recommend that you limit your use of nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen. Frequent and long-term use of these types of medications can increase your risk for peptic ulcer disease. Your doctor may suggest that you take acetaminophen instead. However, you shouldn’t stop taking any medicines without speaking to your doctor first.

Making some lifestyle adjustments can also help reduce peptic ulcer symptoms. These include:

  • limiting alcohol consumption
  • avoiding spicy foods
  • reducing stress
  • smoking cessation

If you have GERD or acid reflux, lifestyle remedies that can ease symptoms include:

  • eating several small meals per day instead of three large ones
  • avoiding alcohol, tobacco, and foods and drinks known to trigger symptoms
  • elevating the head of the bed about 6 inches
  • consuming less fat
  • avoiding lying down for at least two hours after eating
  • avoiding snacks before bedtime

Talk to your doctor if your symptoms don’t improve with medication or lifestyle remedies. You may need more aggressive treatment or surgery to eliminate an ulcer or reduce acid reflux.

You should seek prompt medical attention if any of the following symptoms occur:

  • you develop abdominal pain that’s much worse than you’re accustomed to experiencing
  • you develop a high fever
  • you experience vomiting that’s not easily relieved
  • you develop dizziness and lightheadedness

These are signs of complications from peptic ulcer disease that need to be addressed immediately.



Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.
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