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Drug Details
Zantac 75 Tablets
- Drug Class Description
rapidly acting histamine H2-antagonist - Generic Name
ranitidine hydrochloride - Presentation
Tablet - Description
Quantities per tablet Active Ingredient: Ranitidine Hydrochloride 84mg (equivalent to ranitidine 75mg) - Indications
Symptomatic relief of heartburn, indigestion, acid indigestion and hyperacidity.
For prevention of acid indigestion, indigestion, hyperacidity and heartburn associated with consuming food and drink.
- Adult Dosage
Route of Administration
Oral
Dosage
Adults (including the elderly) and children 16 years of age and older:
Swallow one Zantac 75 tablet whole, with a drink of water, as soon as you have symptoms. If symptoms persist for more than one hour or return, take another tablet. Do not take more than four tablets in 24 hours.
For prevention of acid indigestion, indigestion, hyperacidity and heartburn associated with consuming food and drink, swallow one tablet with water, half to one hour beforehand.
Patients will be advised not to take the tablets for more than 2 weeks continuously and to consult their doctor if symptoms get worse or persist after 2 weeks treatment.
- Child Dosage
Children under 16 years
Not recommended for children under 16 years of age.
- Contra Indications
Ranitidine is contraindicated for patients known to be hypersensitive to the drug or any of the ingredients of Zantac 75 tablets.
- Special Precautions
Treatment with a histamine H2-antagonist may mask symptoms associated with carcinoma of the stomach and may therefore delay diagnosis of the condition.
Ranitidine is excreted via the kidney and so plasma levels of the drug are increased in patients with renal impairment (creatinine clearance less than 50 ml/min). Zantac 75 is not suitable for these patients without medical supervision.
Patients who are taking non-steroidal anti-inflammatory drugs especially in those with a history of peptic ulcer and the elderly should be referred to their doctor before taking Zantac 75. Current evidence shows that ranitidine protects against NSAID associated ulceration in the duodenum and not in the stomach.
Although clinical reports of acute intermittent porphyria associated with ranitidine administration have been rare and inconclusive, ranitidine should be avoided in patients with a history of this condition.
The Patient Information Leaflet and Label advises the patient not to take the maximum daily dose for more than 14 consecutive days unless advised by their doctor.
The product is not indicated in the following patients without seeking their doctor's or pharmacist's advice:
• Patients with renal impairment (creatinine clearance less than 50 ml/min) and/or hepatic impairment.
• Patients under regular medical supervision for other reasons.
• Patients suffering from any other illness or taking medications either physician prescribed or self prescribed.
• Patients of middle age or older with new or recently changed symptoms of indigestion.
• Patients with unintended weight loss in association with symptoms of indigestion.
In patients such as the elderly, persons with chronic lung disease, diabetes or the immunocompromised, there may be an increased risk of developing community acquired pneumonia.
A large epidemiological study showed an increased risk of developing community acquired pneumonia in current users of ranitidine alone versus those who had stopped treatment, with an observed adjusted relative risk increase of 1,82 (95% CI 1,26-2,64).
- Interactions
Ranitidine has the potential to affect the absorption, metabolism or renal excretion of other drugs. The altered pharmacokinetics may necessitate dosage adjustment of the affected drug or discontinuation of treatment.
Interactions occur by several mechanisms including:
1) Inhibition of cytochrome P450-linked mixed function oxygenase system:
Ranitidine at usual therapeutic doses does not potentiate the actions of drugs which are inactivated by this enzyme such as diazepam, lidocaine, phenytoin, propranolol and theophylline.
There have been reports of altered prothrombin time with coumarin anticoagulants (e.g. warfarin). Due to the narrow therapeutic index, close monitoring of increased or decreased prothrombin time is recommended during concurrent treatment with ranitidine.
2) Alteration of gastric pH:
The bioavailability of certain drugs may be affected. This can result in either an increase in absorption or a decrease in absorption.
- Adverse Drug Reactions
The following convention has been utilised for the classification of undesirable effects: very common (>1/10), common (>1/100, <1/10), uncommon (>1/1000, <1/100), rare (>1/10,000, <1/1000), very rare (1/10,000).
Adverse event frequencies have been estimated from spontaneous reports from post-marketing data.
Blood & Lymphatic System Disorders
Very Rare:
Blood count changes (leucopenia, thrombocytopenia). These are usually reversible. Agranulocytosis or pancytopenia, sometimes with marrow hypoplasia or marrow aplasia.
Immune System Disorders
Rare:
Hypersensitivity reactions (urticaria, angioneurotic oedema, fever, bronchospasm, hypotension and chest pain).
Very Rare:
Anaphylactic shock
These events have been reported after a single dose.
Psychiatric Disorders
Very Rare:
Reversible mental confusion, depression and hallucinations.
These have been reported predominantly in severely ill and elderly patients.
Nervous System Disorders
Very Rare:
Headache (sometimes severe),dizziness and reversible involuntary movement disorders.
Eye Disorders
Very Rare:
Reversible blurred vision.
There have been reports of blurred vision, which is suggestive of a change of accommodation.
Cardiac Disorders
Very Rare:
As with other H2 receptor antagonists bradycardia and A-V Block.
Vascular Disorders
Very Rare:
Vasculitis.
Gastrointestinal Disorders
Very Rare:
Acute pancreatitis. Diarrhoea.
Uncommon:
Abdominal pain, constipation, nausea. (these symtoms mostly improved during continued treatment).
Hepatobiliary Disorders
Rare:
Transient and reversible changes in liver function tests.
Very Rare:
Hepatitis (hepatocellular, hepatocanalicular or mixed) with or without jaundice, these were usually reversible.
Skin and Subcutaneous Tissue Disorders
Rare:
Skin Rash.
Very Rare:
Erythema multiforme, alopecia.
Musculoskeletal and Connective Tissue Disorders
Very Rare:
Musculoskeletal symptoms such as arthralgia and myalgia.
Renal and Urinary Disorders
Very rare:
Acute interstitial nephritis.
Rare:
Elevation of plasma creatinine (usually slight; normalised during continued treatment)
Reproductive System and Breast Disorders
Very Rare:
Reversible impotence. Breast symptoms and breast conditions (such as gynaecomastia and galactorrhea).