Ranitidine: Dosage And Precautions

Today we are going to talk about the dosage and precautions of ranitidine. Ranitidine is an antihistamine with a specific and rapid effect. It reduces the secretion of stomach acid, both the amount excreted and the baseline.

In this way, ranitidine decreases the volume and amount of acid and pepsin secreted. The effects are quite long lasting. This is why a single 150mg dose can effectively reduce gastric acid secretion for 12 hours. So what else do you need to know about ranitidine? Read on and we’ll give you all the information.

A brief history of ranitidine

The pharmaceutical company Glaxo developed this drug based on cimetidine, the first antihistamine they developed. In this way ranitidine was the result of a design process. Researchers wanted to refine the compound by replacing certain chemical groups.

With these results, they were then able to synthesize ranitidine, which has a better tolerance profile. That is, the side effects of the medication are much less.

It also offers a long-lasting effect and a 4 to 10 times greater effect than cimetidine. It came on the market in 1981 and was the top-selling prescription drug in 1988. Since then, it has been replaced by even more effective drugs for these indications.

What is histamine?

Histamine is a substance belonging to the chemical family of imidazoles, which is involved in localized immune responses. It also regulates normal functions in the stomach and acts as a neurotransmitter in the central nervous system.

Neurotransmitters are substances that the body makes naturally, whose main function is to regulate the synapses between neurons. In other words, they regulate the chemical reactions between neurons when they transmit signals.

In this way the electrical connections become more complete and many more possibilities arise. If neurotransmitters didn’t exist and neurons just acted like “wires,” the nervous system wouldn’t be able to perform many of its functions.

On the other hand, there is new evidence showing that histamine also plays a role in the chemotaxis of white blood cells, such as eosinophils. Scientists have known about histamine since the 1950s. However, they have only recently discovered its functions in the body.

Indications

The indications for this drug are related to its ability to antagonize histamine H2 receptors. Below we can mention the following, among others:

• Ulcer of the duodenum.
• Benign ulcer.
• Gastric reflux and treatment of associated symptoms.
• Zollinger-Ellison syndrome.
• Treatment of esophageal and gastric bleeding with hypersecretion and prevention of recurrent bleeding in patients with bleeding ulcer.

In addition to the above indications, doctors also prescribe ranitidine for the prevention of gastrointestinal bleeding caused by stress ulcers in the critically ill.

It is also administered preoperatively to patients at risk of acid aspiration syndrome, known as Mendelson’s syndrome. In addition, doctors often give it to mothers during childbirth.

Dosage

Ranitidine is an oral drug. If this method cannot be used, vials are available for intravenous or intramuscular injection. However, doctors usually only resort to this route of administration in a hospital setting. Depending on the indication for which ranitidine is prescribed, the concentration will vary.

• Duodenal ulcer in adults: The dose is 150 mg every 12 hours or 300 mg at night for 4-6 weeks. For children, it is 2 mg per kilogram of body weight every 12 hours.
• Peptic ulcer in adults: 150 mg every 12 hours or 300 mg at night for 6-8 weeks. For associated symptoms, the dose is 150 mg every 12 hours for 2 weeks and treatment may be extended if the initial response is weak.

• Zollinger-Ellison syndrome: The starting dose is 150 mg every 8 hours. The doctor may increase the dose incrementally depending on the patient’s response. However, the maximum dose for this drug is 6 grams per day.

For other indications, the package leaflet of the medicine should be consulted. It contains all the important information regarding ranitidine.

Precautions When Using Ranitidine

Before using ranitidine, it is important to be aware of possible side effects and contraindications and to take appropriate precautions.

When using ranitidine, patients in various situations requiring dose adjustment should take precautions to avoid serious complications. So that’s the case for patients with some of the following conditions:

• Renal insufficiency: the dose must be adjusted.
• Interference in the diagnosis of carcinoma: Ranitidine may delay the symptoms of this type of cancer, which can delay the diagnosis.
• Interference with other diagnostic tests.
• Pregnancy and breastfeeding.

Conclusion

In summary, ranitidine is a drug that is widely used. It is an antihistamine that can be obtained by prescription from a doctor. Patients should follow their physician’s recommendations for use. This drug is not free from side effects and can cause a number of complications.