Ranitidine is an active ingredient used to protect the stomach. It belongs to the group of H2 antagonists. This means that ranitidine attaches to the receptors called “H2” in the stomach and blocks them. The same group of drugs also includes famotidine, roxatidine, nizatidine, and the previously used cimetidine. Only ranitidine and famotidine are available over the counter at low doses. For higher doses with this active ingredient, the drugs require a prescription.
How ranitidine works
Stomach acid is produced in the lining cells of the stomach. Agents such as ranitidine suppress the formation of stomach acid by competing with histamine at H2 receptors called histamine-2 receptors. Histamine activates acid formation and the release of digestive enzymes. H2 antagonists, on the other hand, inhibit acid formation and thus digestion. This protects the stomach. Ranitidine thus acts in the opposite direction (antagonistically) to histamine at the stomach’s H2 receptor. This is why the drug is also called an H2 receptor antagonist. With the help of ranitidine, gastric juice neutralizes itself in this way. This makes it less dangerous and aggressive toward the stomach and adjacent organs such as the esophagus and small intestine.
When does it come into use?
Thus, on the one hand, already existing mucosal inflammation or mucosal injury can heal better. And in addition, the stomach can be protected from the emergence of such inflammations in exceptional situations, when the body is under severe stress. In which situations can this be the case? For example, if our body is under stress because of an operation or during a long hospital stay, the stomach tends to produce more acid. This is prevented with the help of ranitidine.
Side effects of therapy with ranitidine
Ranitidine is considered safe and well tolerated. Only rarely do side effects occur, such as gastrointestinal symptoms like nausea and diarrhea or headache, joint and muscle pain, as well as dizziness and cardiac arrhythmias. It is important to note, however, that ranitidine should not be taken in cases of severe liver dysfunction and the disease called porphyria.
Second choice only
Despite ranitidine’s good tolerability, it is only the second-choice agent for gastric protection outside the hospital. This is partly because the effect of ranitidine is much less than that of the more commonly used proton pump inhibitors (PPIs). In addition, after stopping ranitidine, there is often the problem that the stomach then produces all the more acid and inflammation that has already healed flares up again.
Interactions
Ranitidine is absorbed through the stomach lining. If gastritis is treated with antacids or sucralfate at the same time, this may worsen the absorption of ranitidine. Therefore, ranitidine must be taken two hours before the above medications. Because ranitidine decreases stomach acid production, this changes the pH in the stomach. Other medications, such as the antifungal drug ketoconazole, which are absorbed in the stomach in a pH-dependent manner, may therefore require a different dosage.
Alternatives to ranitidine
Alternatives to ranitidine and H2 antagonists include:
- Proton pump inhibitors
- M1 antagonists (they also inhibit acid production, but by a different mechanism)
- Mucosa-protecting agents that produce increased mucus to protect the stomach from acid, e.g., sucralfate
- Antacids: substances that neutralize stomach acid, this includes the well-known household remedy sodium bicarbonate (sodium hydrogen carbonate), but its use is now no longer recommended
Proper dosage and application
Ranitidine may be used for children after consultation with the attending physician. Depending on the manufacturer’s information, age information is given for children from two, from three or from ten years. In adults, usual dosages of ranitidine are one 300 mg tablet before bedtime for existing stomach or small intestinal ulcer. Alternatively, 150 mg each can be taken in the morning and evening. To protect the stomach and small intestine as a precaution in the case of an ulcer that has already healed, 150 mg of ranitidine in the evening is sufficient. Since ranitidine is excreted mainly through the kidney, special care must be taken in people with chronic kidney failure.Therefore, if the kidney is no longer working well or is even on the verge of failure, the amount of ranitidine must be significantly reduced. Please discuss exact dosages with your treating physician.
Ranitidine during pregnancy
Pregnancy and Breastfeeding: Previous studies on ranitidine during pregnancy have not shown any harmful effects on the unborn child. Nevertheless, before taking it during pregnancy, a detailed discussion should be held with the attending physician to weigh the risks and benefits. Because ranitidine is excreted into breast milk, use during breastfeeding should be avoided.
