COMPOSITION
Each tablet contains Ranitidine Hydrochloride BP equivalent to Ranitidine 150 mg.
PHARMACOLOGICAL INFORMATION
Mechanism of action
Ranitidine (Gastroloc) is a group of H2-receptor antagonist. It acts by blocking histamine receptors which are present on the cells in the stomach lining. Generally a substance called histamine binds to these receptors. Histamine is a chemical, produced throughout the body and has many effects. When histamine binds to H2 receptors on cells in the stomach lining, it causes them to produce acid. Ranitidine (Gastroloc) binds to H2 receptors, replacing some of the histamine. As a result, the amount of stomach acid produced by these cells is decreased. Stomach acid is present as a normal part of the digestive process. If large amounts of stomach acid are produced this can cause the pain in the abdomen commonly known as indigestion. The excess acid may also flow back into the food pipe (oesophagus) causing pain and a burning sensation known as heartburn. Normally the lining of the stomach and duodenum (an area of the intestine directly after the stomach) have a protective layer which resists acid attack. If this layer is damaged, or large amounts of stomach acid are formed, a peptic ulcer develop. Ranitidine (Gastroloc) decreases the amount of acid in the stomach and duodenum. As a result, Ranitidine (Gastroloc) helps relieve the symptoms of indigestion and aids the healing of ulcers. It is also used to depress acid production in various other conditions.
PHARMACOKINETICS
Absorption
Ranitidine (Gastroloc) is 50% absorbed after oral administration, compared to an intravenous (IV) injection with mean peak levels of 440 to 545 mg/mL occurring 1 to 3 hours after a 150-mg dose. Absorption is not significantly impaired by the administration of food or antacids. Propantheline slightly delays and increases peak blood levels of Ranitidine (Gastroloc), probably by delaying gastric emptying and transit time. Simultaneous administration of high-potency antacid (150 mmol) in fasting subjects has been reported to decrease the absorption of Ranitidine (Gastroloc).
Distribution
The volume of distribution is about 1.4 L/kg. Serum protein binding averages 15%.
Metabolism
In humans, the N-oxide is the principal metabolite in the urine; however, this amounts to <4% of the dose. Other metabolites are the S-oxide (1%) and the desmethyl Ranitidine (Gastroloc) (1%). The remainder of the administered dose is found in the stool. Studies in patients with hepatic dysfunction (compensated cirrhosis) indicate that there are minor, but clinically insignificant, alterations in Ranitidine (Gastroloc) half-life, distribution, clearance, and bioavailability.
Excretion
The principal route of excretion is the urine, with approximately 30% of the orally administered dose collected in the urine as unchanged drug in 24 hours. Renal clearance is about 410 mL/min, indicating active tubular excretion. The elimination half-life is 2.5 to 3 hours.
CLINICAL INFORMATION
Therapeutic Indications
Ranitidine (Gastroloc) is indicated in the treatment of Gastric and Duodenal ulcer (Peptic Ulcer), Esophageal Reflux Diseases, Zollinger-Ellison Syndrome, Dyspepsia, Recurrent Ulcer, NSAID Gastropathy and ,In such condition where gastric acidity reduction is beneficial.
2-4 mg/kg twice daily, maximum 300 mg dailyPeptic ulcer150 mg 3 times daily and the dose is increased if necessary up to 6 g daily in divided dosesZollinger-Ellison Syndrome 150 mg twice daily for up to 8 weeks and if necessary for up to 12 weeksReflux Oesophagitis150 mg twice daily for up to 8 weeksNSAID-associated Ulcer150 mg twice daily for up to 6 weeksChronic Episodic DyspepsiaThe usual adult dosage is 150 mg twice daily taken in the morning and evening for up to 4 to 8 weeksBenign Gastric and Duodenal Ulcer Dosage RegimenIndicationChildrenAdultPatient GroupDoses and Administration
Use in Pregnancy & Lactation
Pregnancy
This drug should be used during pregnancy only if clearly needed.
Lactation
Ranitidine (Gastroloc) is secreted in human milk. Caution should be exercised when Ranitidine (Gastroloc) is administered to a nursing mother.
Side effects
Ranitidine (Gastroloc), the following side effects are observed. Minor: headache, dizziness, nausea, stomach pain, constipation, rash. Major: weakness, fever, sore throat, abnormal skin bruising, yellow color to skin or eyes, confusion, agitation. Contraindications
Ranitidine (Gastroloc) is contraindicated for patients known to have hypersensitivity to the drug or any of the ingredients.
Precautions
Symptomatic response to therapy with Ranitidine (Gastroloc) does not preclude the presence of gastric malignancy. Since Ranitidine (Gastroloc) is excreted primarily by the kidney, dosage should be adjusted in patients with impaired renal function . Caution should be observed in patients with hepatic dysfunction since Ranitidine (Gastroloc) is metabolized in the liver. Rare reports suggest that Ranitidine (Gastroloc) may precipitate acute porphyric attacks in patients with acute porphyria. Ranitidine (Gastroloc) should therefore be avoided in patients with a history of acute porphyria.
Drug Interactions
Interaction generally means that one drug may increase or decrease the effect of another drug. Also, the more medications a person takes, the more likely there will be a drug interaction. Interactions with this drug may occur with the following: antacids, blood thinners, diazepam, glipizide, glyburide, itraconazole, ketoconazole, metoprolol, nifedipine, phenytoin, procainamide, sucralfate, theophylline.
PHARMACEUTICAL INFORMATION
Storage conditions
Store in a cool and dry place away from light. Keep out of reach of children.
Presentation & Packaging
GastrolocTM Tablet: Each commercial box contains 100 tablets in Alu-Alu pack. |