Ranitidine

Common Uses

Ranitidine belongs to a class of drugs known as H2 blockers. It works by decreasing the amount of acid produced in the stomach to manage various digestive issues.

Prescription Indications

• Ulcers: It is used to treat active duodenal ulcers and benign gastric ulcers. It may also be used as maintenance therapy to prevent these ulcers from returning after they have healed.
• Gastroesophageal Reflux Disease (GERD): Ranitidine is used to treat the symptoms of acid reflux, where stomach acid flows back into the esophagus.
• Erosive Esophagitis: It is used to treat and provide relief from damage or inflammation in the lining of the esophagus caused by stomach acid.
• Hypersecretory Conditions: It is prescribed for rare conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome.

Over-the-Counter Uses

In lower strengths, this medication was used to prevent and relieve symptoms of heartburn, acid indigestion, and sour stomach caused by eating or drinking certain foods and beverages.

Market Status

In 2020, the FDA requested the removal of all ranitidine products from the market due to concerns regarding a contaminant called NDMA. While some products with similar names have since returned to the market, they have been reformulated with different active ingredients and no longer contain ranitidine.

Mechanism of Action

Ranitidine belongs to a group of medicines called histamine-2 (H2) blockers. It works by targeting specific receptors, called H2 receptors, located on the cells in the lining of the stomach.

Blocking Acid Production

Under normal conditions, a natural chemical in the body called histamine attaches to these H2 receptors. This action signals the stomach to release acid to help digest food. Ranitidine works by competing with histamine for these receptor sites. When ranitidine occupies the receptors, it prevents histamine from binding to them, which effectively blocks the signal to produce acid.

Effects on the Body

By lowering the volume and concentration of stomach acid, ranitidine helps to:

• Relieve symptoms: It reduces the burning sensation associated with heartburn and acid indigestion.
• Promote healing: Lower acid levels allow the lining of the esophagus and stomach to recover from irritation or damage caused by acid reflux.
• Treat and prevent ulcers: It provides an environment that allows stomach or intestinal ulcers to heal and can help prevent them from returning.

Ranitidine starts to work shortly after it is taken to decrease the production of new acid. However, it does not neutralize the acid that is already present in the stomach, which is how liquid or chewable antacids typically function.

Common Side Effects

The most frequently reported side effect of ranitidine is headache. Other common side effects may include:

• Nausea and vomiting
• Stomach pain or abdominal discomfort
• Diarrhea or constipation
• Dizziness or drowsiness
• Insomnia

Serious Side Effects

While less common, some side effects require immediate medical attention. Contact a healthcare provider if you experience:

• Mental health changes, such as confusion, agitation, depression, or hallucinations
• Irregular, fast, or slow heartbeat
• Blurred vision
• Signs of liver problems, including yellowing of the skin or eyes (jaundice), dark urine, or loss of appetite
• Easy bruising or bleeding
• Severe skin rash or hives

In 2020, the FDA requested the removal of all ranitidine products from the market. This was due to concerns regarding a contaminant called NDMA, a probable human carcinogen, which was found to increase in the medication over time and when stored at higher temperatures.

FDA Market Withdrawal

In April 2020, the U.S. Food and Drug Administration (FDA) requested the immediate removal of all prescription and over-the-counter ranitidine products from the market. This decision followed investigations showing that a contaminant known as N-Nitrosodimethylamine (NDMA) can increase in the medication over time, especially when stored at temperatures higher than room temperature. NDMA is classified as a probable human carcinogen.

Contraindications

Ranitidine is contraindicated in patients known to have a hypersensitivity to the drug or any of its components. Cross-sensitivity has been observed in this class of compounds; therefore, caution is advised for individuals with a history of hypersensitivity to other H2-receptor antagonists.

Precautions and Monitoring

• Kidney and Liver Function: Because ranitidine is primarily excreted by the kidneys, dosage adjustments are necessary for individuals with moderate to severe renal impairment. Caution is also advised for those with hepatic dysfunction.
• Gastric Malignancy: A positive response to ranitidine therapy does not exclude the possibility of gastric malignancy. Further diagnostic testing may be required if symptoms persist or recur.
• Porphyria: Clinical reports suggest that ranitidine may precipitate acute porphyric attacks in patients with a history of acute porphyria. Its use should be avoided in these individuals.
• Vitamin B12 Deficiency: Long-term use of acid-suppressing medications like ranitidine may interfere with the absorption of vitamin B12 from the diet, potentially leading to a deficiency over time.
• Phenylketonuria (PKU): Some formulations of ranitidine, such as effervescent tablets, may contain phenylalanine. Individuals with phenylketonuria should be aware of the phenylalanine content in specific products.

Pregnancy

Ranitidine is generally considered to have no known risk of causing birth defects or other developmental issues in humans based on limited data. Animal reproduction studies using doses significantly higher than human doses have not shown evidence of impaired fertility or harm to the fetus. However, there are no adequate and well-controlled studies in pregnant women. Because animal studies are not always predictive of human response, ranitidine should be used during pregnancy only if a healthcare provider determines it is clearly necessary.

Breastfeeding

Ranitidine is excreted in human breast milk. The clinical significance of this exposure to a nursing infant is not fully understood. Caution should be exercised when ranitidine is administered to someone who is breastfeeding. It is important to discuss the potential risks and benefits with a healthcare professional before using this medication while nursing.

Market Status and Safety

In 2020, the FDA requested the removal of all ranitidine products from the U.S. market due to concerns about N-Nitrosodimethylamine (NDMA) contamination. NDMA is a substance that could potentially cause cancer. Individuals who are pregnant or breastfeeding and were previously using ranitidine should consult their healthcare provider for information on alternative treatments that are currently available and approved for use.

Available Forms Before Market Removal

Before its removal from the market, ranitidine was available in the following forms:

• Oral tablets
• Oral capsules
• Effervescent tablets
• Effervescent granules
• Oral syrup (liquid)
• Injectable solution

Current Market Status

The U.S. Food and Drug Administration (FDA) requested the removal of all prescription and over-the-counter ranitidine products from the market. This action was taken after testing found a contaminant that could increase over time and when stored at higher temperatures. As a result, these forms are no longer available for use.

Market Withdrawal

In April 2020, the U.S. Food and Drug Administration (FDA) requested that manufacturers withdraw all prescription and over-the-counter (OTC) ranitidine medications from the market. This regulatory action was taken because of the presence of N-Nitrosodimethylamine (NDMA), an impurity classified as a probable human carcinogen, in some ranitidine products.

Safety Findings

FDA investigations determined that NDMA levels in ranitidine can increase over time, especially when the medication is stored at temperatures higher than room temperature. Testing showed that the older a ranitidine product is, or the longer it has been since it was manufactured, the higher the level of NDMA may be. These levels could potentially exceed acceptable daily intake limits, leading the FDA to conclude that the drug should no longer be available to consumers.

Current Status and Alternatives

Ranitidine is currently not available for sale in the United States. The FDA advised patients to stop taking any ranitidine they had and to consult with healthcare professionals about alternative treatments. Other acid-reducing medications, such as famotidine, cimetidine, and omeprazole, have not been found to contain NDMA and remain available for use. Some products previously sold under brand names associated with ranitidine have been reformulated with different active ingredients that do not carry the same risks.

Reason for the Recall

The market withdrawal was prompted by the discovery of a contaminant called N-Nitrosodimethylamine (NDMA) in ranitidine medications. NDMA is classified as a probable human carcinogen, which is a substance that could potentially cause cancer in humans.

Contamination Risks

FDA testing revealed that the levels of NDMA in ranitidine can increase over time, even when the medication is stored under normal conditions. Furthermore, NDMA levels were found to increase significantly when the drug was exposed to higher temperatures. Because the FDA could not guarantee that NDMA levels would remain within safe limits throughout the shelf life of the product, all versions of the drug were removed from the market.

Guidance for Patients

If you have ranitidine in your possession, you should follow these safety steps:

• Stop taking the medication: Do not use any remaining ranitidine tablets, capsules, or liquids.
• Dispose of the drug properly: Follow the disposal instructions on the product label or consult a pharmacist for guidance on how to safely discard the medication.
• Seek alternatives: Consult a healthcare provider to discuss other treatment options for acid reflux, heartburn, or ulcers. There are several other medications available that do not carry the same NDMA risks.

It is important to note that while some products with similar brand names have returned to store shelves, they have been reformulated with different active ingredients that were not part of this recall.