Ranitidine is an active ingredient for stomach protection. He belongs to the group of H2-antagonists. This means that ranitidine in the stomach attaches to the receptors called "H2" and blocks them. The same active ingredient group also includes famotidine, roxatidine, nizatidine and the previously used cimetidine. Only ranitidine and famotidine are available in low doses without prescription. For higher dosages with this drug, the drugs are prescription.
How ranitidine works
The gastric acid is produced in the parietal cells of the stomach. Drugs such as ranitidine suppress the formation of gastric acid by competing with histamine at the H2 receptors, the so-called histamine-2 receptors. Histamine activates the acidification and release of digestive enzymes. In contrast, H2-antagonists inhibit the formation of acid and thus digestion. This protects the stomach.
Ranitidine thus acts opposite (antagonistically) to histamine at the H2 receptor of the stomach. Therefore, the drug is also called H2 receptor antagonist. With the help of ranitidine neutralizes the gastric juice in this way. This makes it less dangerous and aggressive to the stomach and adjacent organs such as the esophagus and the small intestine.
When does it apply?
On the one hand, existing mucosal inflammations or mucosal injuries can heal better. In addition, in exceptional situations where the body is under severe stress, the stomach may be protected from the onset of such inflammation.
In which situations can this be the case? For example, if our body is under stress due to surgery or during a long hospital stay, the stomach tends to produce more acid. This is prevented with the help of ranitidine.
Side effects of ranitidine therapy
Ranitidine is considered safe and well tolerated. There are rarely side effects such as gastrointestinal discomfort such as nausea and diarrhea or headache, joint and muscle pain, dizziness and cardiac arrhythmia. It is important to note, however, that in patients with severe liver dysfunction and the disease called porphyria no ranitidine may be taken.
Only second choice
Despite the good tolerability of ranitidine, it is only the remedy of second choice for gastric protection outside the hospital. This is partly because the effect of ranitidine is significantly lower than that of the more commonly used proton pump inhibitors (PPIs). In addition, after discontinuing ranitidine, there is often the problem that the stomach produces more acid and inflammation that has already healed.
Ranitidine is taken up via the gastric mucosa. Treating gastritis simultaneously with antacids or sucralfate may worsen the uptake of ranitidine. Therefore, ranitidine must be taken two hours before the mentioned drugs.
Since ranitidine reduces gastric acid production, this changes the pH in the stomach. Other medications, such as the fungicidal agent ketoconazole, which are taken up in the stomach for pH-dependent purposes, may therefore require a different dosage.
Alternatives to ranitidine
Alternatives to ranitidine and H2-antagonists are:
- Proton pump inhibitors
- M1 antagonists (they also inhibit acid production, but with the help of another mechanism)
- Mucosal protective agents that produce increased mucus to protect the stomach from the acid, eg sucralfate
- Antacids: Substances that neutralize stomach acid, including the well-known home remedy Sodium (sodium bicarbonate), the application of which is now no longer recommended
Proper dosage and application
Ranitidine may also be used for children after consultation with the attending physician. Depending on the manufacturer's information, ages are given for children from two to three or ten years and older. In adults, usual dosages of ranitidine are a 300 mg tablet at bedtime in the presence of gastric or small bowel ulcer. Alternatively, 150 mg can be taken each morning and evening. As a precautionary measure to protect the stomach and small intestine from an already healed ulcer, 150 mg of ranitidine are sufficient in the evening.
Since ranitidine is excreted mainly via the kidney, special care must be taken in people with chronic kidney failure. If the kidney is not working well or is even close to failure, the amount of ranitidine must therefore be significantly reduced. Exact doses should be discussed with your doctor.
Ranitidine in pregnancy
Pregnancy and breast-feeding: Previous studies on ranitidine during pregnancy have shown no adverse effects on the unborn baby. Nevertheless, a detailed discussion should be held with the attending physician before taking it during pregnancy for a risk-benefit analysis. Since ranitidine is excreted in breast milk, intake should be avoided during breast-feeding.