Ranitidine is a member of the class of histamine H2-receptor antagonists with antacid activity. Ranitidine is a competitive and reversible inhibitor of the action of histamine, released by enterochromaffin-like (ECL) cells, at the histamine H2-receptors on parietal cells in the stomach, thereby inhibiting the normal and meal-stimulated secretion of stomach acid. In addition, other substances that promote acid secretion have a reduced effect on parietal cells when the H2 receptors are blocked.
Mechanism of Action of Ranitidine
Indications of Ranitidine
- Used in the treatment of peptic ulcer disease (PUD), dyspepsia, stress ulcer prophylaxis, and gastroesophageal reflux disease (GERD).
- For the treatment of acid-reflux disorders (GERD), peptic ulcer disease, H. pylori eradication, and prevention of gastroinetestinal bleeds with NSAID use.
- To treat symptoms of GORD such as heartburn and acid regurgitation
- Gastroesophageal reflux disease (GERD)
- Erosive esophagitis (acid-related damage to the esophagus, the tube that connects your mouth to your stomach)
- Gastric (stomach) ulcers or duodenal ulcers. Duodenal ulcers occur in your duodenum. This is the first part of your small intestine. It is the part connected to your stomach.
- Conditions where your stomach makes too much acid, such as Zollinger-Ellison Syndrome
- Stomach infections caused by Helicobacter pylori bacteria.
- Ulcers in the upper part of the intestine (duodenal ulcer) or stomach (gastric ulcer).
- Ulcers caused by medicines called NSAIDs (Non-Steroidal Anti-Inflammatory Drugs).
- Too much acid in the stomach caused by a growth in the pancreas (Zollinger-Ellison syndrome).
- Benign gastric ulcers
- Heartburn and other symptoms associated with GERD,
- Erosive esophagitis, and long-term treatment of pathological hypersecretory conditions
- Multiple endocrine adenomas,
- Systemic mastocytosis.
- Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of acute ulcers. No placebo-controlled comparative studies have been carried out for periods of longer than 1 year.
- The treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome and systemic mastocytosis).
- Short-term treatment of active, benign gastric ulcer. Most patients heal within 6 weeks and the usefulness of further treatment has not been demonstrated. Studies available to date have not assessed the safety of ranitidine in uncomplicated, benign gastric ulcer for periods of more than 6 weeks.
- Maintenance therapy for gastric ulcer patients at reduced dosage after healing of acute ulcers. Placebo-controlled studies have been carried out for 1 year.
- Symptomatic relief commonly occurs within 24 hours after starting therapy with ranitidine 150 mgtwice daily
- Prevention of stress-induced ulcers in critically ill patients
- Recurrent postoperative ulcer
- Treatment of endoscopically diagnosed erosive esophagitis. Symptomatic relief of heartburn commonly occurs within 24 hours of therapy initiation with ranitidine 150 mg4 times dailyd.
- Maintenance of healing of erosive esophagitis. Placebo-controlled trials have been carried out for 48 weeks.
Therapeutic of Ranitidine
- Anti-Ulcer Agents
- Ranitidine is effective for the treatment of duodenal or gastric ulcer and relieves symptoms of reflux esophagitis. It heals some NSAID-induced ulcers but does not appear to prevent their initial occurrence.
- Investigationally, this drug prevented aspiration pneumonitis during surgery, and it appears to be useful for the prophylaxis of bleeding due to stress ulcers.
- Studies show that ranitidine can adequately inhibit acid secretion in patients with gastric hypersecretory disorders, is safe at high doses, does not cause the antiandrogen side effects frequently seen with high doses of cimetidine, & is threefold more potent than cimetidine. Patients relatively resistant to cimetidine will have proportional resistance to ranitidine.
- Ranitidine and a placebo were evaluated in the 28 day treatment of duodenal ulcer through an open randomized study performed in 120 patients. At the end of the treatment, ranitidine demonstrated a significantly higher efficacy on ulcer healing as well as on symptom relief in comparison with placebo .
- Parenteral ranitidine is used to prevent and treat upper gastrointestinal, stress-induced ulceration and bleeding, especially in intensive care patients. However, the efficacy of histamine H2-receptor antagonists in treating hemorrhage in critically ill patients has not been established.
- Histamine H2-receptor antagonists are indicated in the short-term treatment of active duodenal ulcer. They are also indicated (at reduce dosage) in the prevention of duodenal ulcer recurrence in selected patients.
- Ranitidine is indicated in the short-term treatment of active benign gastric ulcer.
- Rantidine is indicated in the treatment of pathological gastric hypersecretion associated with Zollinger-Ellison syndrome (alone or as part of multiple endocrine neoplasia Type-1), systemic mastocytosis, and multiple endocrine adenoma.
- Ranitidine is indicated in the treatment of acute gastroesophageal reflux disease, which may or may not cause erosion or ulcerative esophagitis.
- Ranitidine is used to treat upper gastrointestinal bleeding secondary to gastric ulcer, duodenal ulcer, or hemorrhagic gastritis.
- Histamine H2-receptor antagonists are not recommended for minor digestive complaints.
- Ranitidine is also used before anesthesia induction for the prophylaxis of aspiration pneumonitis.
Contra Indications of Ranitidine
- People with a known hypersensitivity to PPI , substituted benzimidazoles or any other component of the capsule formulation (e.g. certain dyes)
- Breast feeding women
- People with known hypersensitivity (allergy) to PPI or any of the ingredients in the medication.
- Clostridium difficile infection
- Inadequate Vitamin B12
- Low amount of magnesium in the blood
- Liver problems
- Interstitial Nephritis
- Subacute cutaneous lupus erythematosus
- Systemic Lupus Erythematosus
- Broken Bone
- Allergies to Proton Pump Inhibitors
Side Effects of Ranitidine
The most common
- Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain.
- Drowsiness and lightheadedness
- Numbed emotions.
- Visual disturbances such as blurred vision or double vision.
- Shaky movements and unsteady walk (ataxia).
- Loss of memory (amnesia).
- Muscle weakness.
- Skin rashes.
- Difficulty in passing urine (urinary retention).
- Changes in sex drive.
- Low blood pressure (hypotension).
- Blood disorders.
- Unexpected aggression, restlessness or irritability
- Nightmares or hallucinations
- Loss of muscle coordination
- Sleepiness or unusual drowsiness
- Clumsiness or unsteadiness
- Dry mouth
- Muscle weakness.
- Skin rashes.
- irregular or fast heartbeat
- tremors (jerking movements or shaking)
- muscle weakness
- spasms of the hands and feet
- cramps or muscle aches
- trouble breathing, coughing, wheezing, hoarse voice, or
- throat tightness
- watery stool
- rash on the skin and nose ,raised, red, scaly, red or purple rash on your body
- convulsions (seizures)
- sore throat
- difficulty with breathing
- unusual tiredness or weakness
Drug Interactions of Ranitidine
Ranitidine may interact with following drugs, supplyments, & may change the efficacy of drugs
- “azole” antifungal medications (e.g., itraconazole, fluconazole, ketoconazole, posaconazole)
- bisphosphonates (e.g., alendronate, risedronate)
- certain protein kinase inhibitors (e.g. dasatinib, nilotinib
- iron salts
- “statin” cholesterol medications (e.g., atorvastatin, lovastatin, simvastatin)
Studies in animals have failed to demonstrate a risk to the unborn baby, and there are no well-controlled studies in pregnant women. Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have not shown evidence of an increased occurrence of fetal damage.