Consumer medicine information

Zantac 150 and Zantac 300 Tablets

Ranitidine

BRAND INFORMATION

Brand name

Zantac

Active ingredient

Ranitidine

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Zantac 150 and Zantac 300 Tablets.

SUMMARY CMI

Zantac 150 and Zantac 300 tablets

Consumer Medicine Information (CMI) summary

The full CMI on the next page has more details. If you are worried about using this medicine, speak to your doctor or pharmacist.

1. Why am I using Zantac 150 or Zantac 300 tablets?

Zantac 150 and Zantac 300 tablets contain the active ingredient ranitidine (as ranitidine hydrochloride). Zantac 150 and Zantac 300 are used to treat problems caused in part by too much acid in the stomach; being used to treat and prevent peptic ulcers, and to treat reflux.

For more information, see Section 1. Why am I using Zantac 150 or Zantac 300? in the full CMI.

2. What should I know before I use Zantac 150 and Zantac 300?

Do not use if you have ever had an allergic reaction to ranitidine or any of the ingredients listed at the end of the CMI.

Talk to your doctor if you have any other medical conditions, take any other medicines, or are pregnant or plan to become pregnant or are breastfeeding.

For more information, see Section 2. What should I know before I use Zantac 150 and Zantac 300? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with Zantac 150 and Zantac 300 and affect how it works.

A list of these medicines is in Section 3. What if I am taking other medicines? in the full CMI.

4. How do I use Zantac 150 or Zantac 300 tablets?

  • The normal adult dose is 150 to 300 mg, taken as one 150 mg tablet once or twice a day, or one 300 mg tablet at bedtime.
    The dosage depends on the disease that you are suffering from. Your doctor or pharmacist will tell you how much to take.
  • Zantac 150 and Zantac 300 tablets should be swallowed whole with a glass of water. It does not matter if you take the tablet before or after food.
  • Take Zantac 150 and Zantac 300 tablets for as long as your doctor has prescribed it for.

More instructions can be found in Section 4. How do I use Zantac 150 or Zantac 300 tablets? in the full CMI.

5. What should I know while using Zantac 150 or Zantac 300 tablets?

Things you should do
  • Take all the tablets your doctor has prescribed for you, even if you feel better.
  • Call your doctor immediately if you have taken all of your tablets and still do not feel better.
  • Remind any doctor, dentist or pharmacist you visit that you are using Zantac 150 or Zantac 300.
Things you should not do
  • Do not take extra tablets, and do not take the tablets more often than you have been told.
  • Do not give this medicine to anyone else, even if their symptoms seem similar to yours.
Driving or using machines
  • Be careful before you drive or use any machines or tools until you know how Zantac 150 or Zantac 300 affects you.
Looking after your medicine
  • Keep Zantac 150 and Zantac 300 tablets in the pack until it is time to take them.
  • Keep it in a cool dry place, away from moisture or heat, where the temperature stays below 25°C.

For more information, see Section 5. What should I know while using Zantac 150 or Zantac 300 tablets? in the full CMI.

6. Are there any side effects?

Less serious side effects of Zantac 150 and Zantac 300 include headache, joint or muscle pains, drowsiness, insomnia, dizziness, depression, constipation, feeling sick (nausea) or vomiting, diarrhoea, breast tenderness and/or enlargement, breast discharge, and changes in liver function tests. Serious side effects include severe stomach pain or a change in the type of pain, yellow colouring of the skin or eyes (jaundice), confusion, general illness associated with weight loss, fever, and changes to the heartbeat (including an irregular heartbeat, or an unusually fast or slow heartbeat.). Another serious side effect is an allergic reaction. Signs of an allergic reaction may include: skin reactions e.g. rash (red spots), itching, skin lumps, or hives; swelling of the eyelids, face, lips, tongue, or other parts of the body; shortness of breath, trouble breathing, wheezing, chest pain or tightness; and unexplained fever and feeling faint, especially when standing up.)

For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.



FULL CMI

Zantac 150 and Zantac 300 tablets

Active ingredient: ranitidine (as ranitidine hydrochloride)

Consumer Medicine Information (CMI)

This leaflet provides important information about using Zantac 150 and Zantac 300 tablets. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about using Zantac 150 and Zantac 300 tablets.

Where to find information in this leaflet:

1. Why am I using Zantac 150 or Zantac 300 tablets?
2. What should I know before I use Zantac 150 and Zantac 300?
3. What if I am taking other medicines?
4. How do I use Zantac 150 or Zantac 300 tablets?
5. What should I know while using Zantac 150 or Zantac 300 tablets?
6. Are there any side effects?
7. Product details

1. Why am I using Zantac 150 or Zantac 300 tablets?

Zantac 150 and Zantac 300 tablets contain the active ingredient ranitidine (as ranitidine hydrochloride). It belongs to a group of medicines called H2-antagonists.

Zantac 150 and Zantac 300 are mostly used to:

  • treat stomach and duodenal ulcer disease (also known as peptic ulcer)
  • stop these ulcers from coming back
  • treat reflux oesophagitis (also known as reflux).

These problems are caused, in part, by too much acid in the stomach. This medicine reduces the pain and allows the ulcer and reflux to heal.

Zantac 150 and Zantac 300 are also used to treat:

  • Zollinger-Ellison disease
  • Scleroderma oesophagitis.

2. What should I know before I use Zantac 150 and Zantac 300?

Warnings

Do not use Zantac 150 and Zantac 300 tablets if:

  • you are allergic to ranitidine or any of the ingredients listed at the end of this leaflet.
    - Some symptoms of an allergic reaction may include shortness of breath, wheezing or difficulty in breathing; swelling of the face, lips, tongue, or any other parts of the body; rash, itching or hives on the skin.
    - Always check the ingredients to make sure you can use this medicine. Check with your doctor or pharmacist if you are unsure.
  • the expiry date printed on the pack has passed.
  • the packaging is torn or shows signs of tampering.

Check with your doctor if:

  • you have any other medical conditions, especially the following:
    - stomach cancer
    - kidney disease
    - a history of stomach ulcers, and you are taking Non-Steroidal Anti-Inflammatory medicines (NSAIDs)
    - acute poryphia
    - diabetes
    - problems with your immune system.
  • you take any medicines for any other condition
  • you have had any allergy to any other medicines, or any other substances, such as foods, preservatives, or dyes.
  • you have to stop taking this or any other medicine for your ulcer or reflux.

During treatment, you may be at risk of developing certain side effects. It is important you understand these risks and how to monitor for them. See additional information under Section 6. Are there any side effects?

Pregnancy and breastfeeding

Check with your doctor if you are pregnant, are planning on becoming pregnant, or are breastfeeding. Your doctor will tell you if you should take this medicine.

Use in the elderly

Tell your doctor if you are over 65 years of age before taking this medicine.

Use in children

Zantac 150 and Zantac 300 have not been studied fully in children. However, Zantac 150 and Zantac 300 have been used with good results in children aged 8 to 18 years in doses up to 150 mg twice daily.

3. What if I am taking other medicines?

Tell your doctor or pharmacist if you are taking any other medicines, including any medicines, vitamins or supplements that you buy without a prescription from your pharmacy, supermarket or health food shop.

Zantac 150 and Zantac 300 can affect the way some other medicines work. Also other medicines can affect the way Zantac 150 and Zantac 300 work.

In particular, tell your doctor if you are taking any of the following medicines:

  • warfarin, used to prevent blood clots
  • triazolam and midazolam, used as sedatives
  • ketoconazole, an anti-fungal
  • atazanavir and delaviridine, used to treat HIV
  • glipizide, used for diabetics
  • gefitinib, used in the treatment of cancer.
  • non-steroidal anti-inflammatory medicines (NSAIDs), for pain and inflammation
  • procainamide or n-acetylprocainamide, used to treat heart problems
  • sucralfate used to treat ulcers.

Check with your doctor or pharmacist if you are not sure about what medicines, vitamins or supplements you are taking and if these affect Zantac 150 and Zantac 300.

4. How do I use Zantac 150 or Zantac 300 tablets?

How much to take

  • The dosage depends on the disease that you are suffering from. Your doctor or pharmacist will usually tell you how many Zantac 150 or Zantac 300 tablets to take and how often to take them.
  • The normal adult dosage is 150 to 300 mg per day, taken as one 150 mg tablet once or twice a day, or one 300 mg tablet at bedtime. Your doctor may prescribe a different dosage.

When to take Zantac 150 and Zantac 300 tablets

It does not matter whether you take the tablets before or after food.

How to take Zantac 150 and Zantac 300 tablets

Zantac 150 and Zantac 300 tablets should be swallowed whole with a glass of water.

How long to take Zantac 150 and Zantac 300 tablets for

  • Your pain or other symptoms may take a few days to go away. Take all the tablets your doctor has prescribed for you, even if you feel better.
  • Even when you have completed your tablets, your doctor may decide to continue your treatment with Zantac 150 or Zantac 300, possibly at a different dosage, in order to prevent the problem from coming back again.

If you forget to use Zantac 150 or Zantact 300 tablets

If you forget to take your Zantac 150 or Zantac 300 tablets, take another as soon as possible unless it is nearly time for your next dose.

If it is almost time for your next dose, skip the dose you missed and take your next dose when you are meant to.

Do not take a double dose to make up for the dose you missed.

If you take too many Zantac 150 or Zantac 300 tablets

If you think that you have taken too many Zantac 150 or Zantac 300 tablets, you may need urgent medical attention.

You should immediately:

  • phone the Poisons Information Centre
    (by calling 13 11 26), or
  • contact your doctor, or
  • go to the Emergency Department at your nearest hospital.

You should do this even if there are no signs of discomfort or poisoning.

5. What should I know while using Zantac 150 or Zantac 300 tablets?

Things you should do

  • Take all the tablets your doctor has prescribed for you, even if you feel better.
  • Remind any doctor, dentist or pharmacist you visit that you are using Zantac.

Call your doctor immediately if:

You have taken all the tablets and still do not feel better.

Things you should not do

  • Do not take extra tablets, and do not take the tablets more often than you have been told.
  • Do not give this medicine to anyone else, even if their symptoms seem similar to yours.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how Zantac 150 or Zantac 300 affects you.

Looking after your medicine

  • Keep Zantac 150 and Zantac 300 tablets in the pack until it is time to take them.
  • Keep Zantac 150 and Zantac 300 tablets in a cool dry place, away from moisture or heat, where the temperature stays below 25°C. Heat and dampness can destroy some medicines.
  • Keep it where young children cannot reach it.
    A locked cupboard at least one and a half metres above the ground is a good place to store medicines.

Getting rid of any unwanted medicine

If you no longer need to use this medicine or it is out of date, take it to any pharmacy for safe disposal.

6. Are there any side effects?

All medicines can have side effects. If you do experience any side effects, most of them are minor and temporary. However, some side effects may need medical attention.

See the information below and, if you need to, ask your doctor or pharmacist if you have any further questions about side effects.

Less serious side effects

Less serious side effectsWhat to do
  • headache
  • joint or muscle pains
  • drowsiness
  • insomnia
  • dizziness
  • depression
  • diarrhoea
  • constipation
  • feeling sick (nausea) or vomiting
  • breast tenderness and/or breast enlargement
  • breast discharge
  • changes in blood and liver function tests.
Speak to your doctor if you have any of these less serious side effects and they worry you.

Serious side effects

Serious side effectsWhat to do
  • An allergic reaction. The signs may include:
    - skin reactions such as rash (red spots), itching, skin lumps or hives.
    - Swelling of the eyelids, face, lips, tongue, or other parts of the body.
    - shortness of breath, trouble breathing, wheezing, chest pain or tightness.
    - unexplained fever and feeling faint, especially when standing up.
  • severe stomach pain or a change in the type of pain
  • yellow colouring of the skin or eyes (jaundice)
  • confusion
  • general illness associated with weight loss
  • fever
  • irregular heartbeat (including unusually fast or slow heart beats)
  • changes to heartbeat.
Stop taking Zantac 150 and Zantac 300, and call your doctor straight away or go straight to the Emergency Department at your nearest hospital if you notice any of these serious side effects.

Tell your doctor or pharmacist if you notice anything else that may be making you feel unwell.

Other side effects not listed here may occur in some people.

Reporting side effects

After you have received medical advice for any side effects you experience, you can report side effects to the Therapeutic Goods Administration online at www.tga.gov.au/reporting-problems. By reporting side effects, you can help provide more information on the safety of this medicine.

Always make sure you speak to your doctor or pharmacist before you decide to stop taking any of your medicines.

7. Product details

Zantac 150 and Zantac 300 tablets for these medical uses and in the pack sizes described below are only available with a doctor's prescription.

What Zantac tablets contain

Active ingredient
(main ingredient)
  • ranitidine (as ranitidine hydrochloride
Each Zantac 150 tablet contains 150 mg of ranitidine.
Each Zantac 300 tablet contains 300 mg of ranitidine.
Other ingredients
(inactive ingredients)
  • microcrystalline cellulose
  • magnesium stearate
  • croscarmellose sodium
  • opadry II white YS-22-18096.
Each Zantac 300 tablet contains 0.8 mg of sodium.

Do not take this medicine if you are allergic to any of these ingredients.

Zantac 150 and Zantac 300 tablets are free from gluten and lactose.

What Zantac 150 and Zantac 300 tablets look like

Zantac tablets, available with a doctor's prescription, come in two strengths and in different pack sizes.

Zantac 150 are white, film-coated round tablets embossed with "150" on one face and plain on the other side. Available in blister packs of 60 tablets.

Zantac 300 are white, film-coated capsule shaped tablets embossed with “300” on one side and plain on the other. Available in blister packs of 30 tablets.

Australian registration numbers:

Zantac 150 tablets: (AUST R 427731)

Zantac 300 tablets: (AUST R 53323)

Who distributes Zantac 150 and Zantac 300 tablets?

Aspen Pharmacare Australia Pty Ltd
34-36 Chandos St
St Leonards NSW 2065
Australia

This leaflet was prepared in December 2024.

Published by MIMS February 2025

BRAND INFORMATION

Brand name

Zantac

Active ingredient

Ranitidine

Schedule

S4

 

1 Name of Medicine

Ranitidine hydrochloride.

2 Qualitative and Quantitative Composition

Zantac 150 mg tablets are white film-coated tablets engraved “RAN 150” on one face and plain on the other. The tablets contain 150 mg ranitidine (as hydrochloride).
Zantac 300 mg tablets are white capsule-shaped, film-coated tablets engraved “RAN 300” on one face and plain on the other. The tablets contain 300 mg ranitidine (as hydrochloride).
Zantac 150 mg dispersible tablets are white, capsule-shaped, film-coated tablets with a breakline on one face. The tablets contain 150 mg ranitidine (as hydrochloride). These tablets also contain saccharin sodium as an excipient.
Zantac 150 mg effervescent tablets are white to pale yellow, round, bevelled tablets debossed “GS LHK” on one side and flat on the other. The tablets contain 150 mg of ranitidine (as hydrochloride). Each 150 mg tablet contains 328 mg (14.3 mEq) sodium, as well as aspartame and sodium benzoate as excipients.
Zantac 300 mg effervescent tablets are white to pale yellow, round, bevelled tablets debossed “GS MJG” on one side and flat on the other. The tablets contain 300 mg of ranitidine (as hydrochloride). Each 300 mg tablet contains 479 mg (20.8 mEq) sodium, as well as aspartame and sodium benzoate as excipients.
Zantac oral liquid is a clear pale yellow liquid containing 150 mg ranitidine (as hydrochloride) in each 10 mL. It also contains butyl hydrozybenzoate, propyl hydroxybenzoate, ethanol and saccharin sodium as excipients.
Zantac injection is a clear colourless to pale yellow liquid, practically free from visible particles containing 50 mg ranitidine (as hydrochloride) in 2 mL ampoules.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

See Section 2 Qualitative and Quantitative Composition.

4 Clinical Particulars

4.1 Therapeutic Indications

1. Short-term treatment of proven duodenal ulcer and gastric ulcer, including intravenous use for prophylaxis against recurrent haemorrhage.
2. Maintenance treatment to reduce the risk of relapse in duodenal ulcer.
3. Maintenance treatment for periods up to one year to reduce the risk of relapse in patients with documented healing of benign gastric ulcer.
4. Treatment of gastrinoma (Zollinger-Ellison syndrome).
5. Short-term symptomatic treatment of reflux oesophagitis unresponsive to conservative antireflux measures and simple drug therapies such as antacids.
6. Maintenance treatment to reduce the risk of relapse of reflux oesophagitis.
7. Treatment of scleroderma oesophagitis.
The intravenous injection is indicated where oral treatment is inappropriate.

4.2 Dose and Method of Administration

Zantac may be administered by mouth, by intravenous injection or by slow intravenous infusion.

Zantac tablets, effervescent tablets and oral liquid.

1. Acute duodenal or gastric ulceration. 300 mg taken as a single dose at bedtime, or 150 mg taken twice daily, in the morning and at bedtime.
It is not necessary to time the dose in relation to meals. In most cases healing will occur in four weeks although a small number of patients may require an additional 2-4 weeks of therapy.
2. Maintenance treatment.

2.1 Duodenal ulcer.

150 mg taken at night.
As smoking is associated with a higher rate of ulcer relapse, patients should be advised to stop smoking. In patients unable to stop smoking, a dose of 300 mg at night provides additional therapeutic benefit.

2.2 Gastric ulcer.

150 mg taken at night for a period of one year.
3. Gastrinoma (Zollinger-Ellison syndrome). 150 mg taken 3 times daily initially and increased, as necessary, to 600 to 900 mg/day.
4. Prophylaxis against recurrent haemorrhage in patients bleeding from peptic ulceration. This should be by intravenous injection or infusion.
5. Oesophagitis. 300 mg taken as a single dose at bedtime or 150 mg taken twice daily, in the morning and at bedtime. It is not necessary to time the dose in relation to meals.
In severe reflux oesophagitis the efficacy of 300 mg, taken as a single dose at bedtime, has been established for up to 3 months.
6. Maintenance treatment.

6.1 Reflux oesophagitis.

150 mg taken twice daily, in the morning and at bedtime.

Zantac effervescent tablets.

Zantac effervescent tablets should be placed in half a glass of water (minimum 75 mL) and allowed to dissolve completely before swallowing, swirl the glass if necessary. The effervescent formulations contain aspartame.

Zantac oral liquid.

Zantac oral liquid contains approximately 7.5% w/v ethanol (alcohol), i.e. up to 375 mg per 5 mL spoonful (approximately a teaspoonful).

Zantac injection.

Zantac injection may be given either as a slow intravenous injection of 50 mg (e.g. 2 mL diluted in 20 mL 0.9% sodium chloride and given as a slow injection over not less than 5 minutes), which may be repeated every six to eight hours; or as an intravenous infusion at a rate of 25 mg per hour for two hours; the infusion may be repeated at six to eight hour intervals.

Stability in intravenous infusion fluids.

Zantac injection has been shown to be compatible with the following intravenous infusion fluids: 0.9% Sodium Chloride BP, 5% Glucose BP, 0.18% Sodium Chloride and 4% Glucose BP, 4.2% Sodium Bicarbonate BP and Hartmann's solution. However, Zantac injection does not contain any antimicrobial preservative. To reduce microbial contamination hazards, the admixture should be used as soon as practicable after preparation. All unused admixtures of Zantac injection with infusion fluids should be discarded 24 hours after preparation. Zantac injection should not be autoclaved.

4.3 Contraindications

Patients with known hypersensitivity to any component of the preparation.

4.4 Special Warnings and Precautions for Use

Gastric ulcer.

Treatment with a histamine H2-antagonist may mask symptoms associated with carcinoma of the stomach and, therefore, may delay diagnosis of the condition. Accordingly, where gastric ulcer is suspected, the possibility of malignancy should be excluded before therapy with Zantac oral liquid, tablets or injection is instituted.

Long-term use.

The risk of ulcer recurrence is determined by many factors. In some cases, long periods of treatment may be necessary and/or repeated. Evidence from controlled clinical trials of up to 18 months continuous treatment with Zantac has not revealed any undue untoward effects.

Bradycardia.

In association with rapid administration of Zantac injection, has been reported rarely, usually in patients with factors predisposing to cardiac rhythm disturbances. Recommended rates of administration should not be exceeded.

Higher doses.

The use of higher than recommended doses of intravenous H2-antagonists has been associated with rises in liver enzymes when treatment has been extended beyond five days.

Porphyria.

Rare clinical reports suggest that ranitidine may precipitate acute porphyric attacks. Zantac should, therefore, be avoided in patients with a history of acute porphyria.

Gastric pH.

Agents that elevate gastric pH may increase the already present risk of nosocomial pneumonia in intubated ICU patients receiving mechanical ventilation.
Zantac effervescent tablets contain sodium. Care should, therefore, be taken in treating patients in whom sodium restriction is indicated. As Zantac effervescent tablets contain aspartame they should be used with caution in patients with phenylketonuria.

Pharmaceutical precautions.

Dilution of Zantac oral liquid with Syrup BP or sorbitol solution is not recommended as this may result in precipitation.

Use in renal impairment.

Ranitidine is excreted via the kidney and in the presence of renal impairment plasma levels of ranitidine are increased and prolonged. Accordingly in the presence of significant renal impairment, serum levels should be monitored and dosage adjustments made. The clearance of ranitidine is increased during haemodialysis.

Use in the elderly.

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 H2-receptor antagonists versus those who had stopped treatment, with an observed adjusted relative risk of 1.63 (95% CI, 1.07-2.48).

Paediatric use.

Experience with ranitidine tablets in children is limited and such use has not been fully evaluated in clinical studies. It has however, been used successfully in children aged 8-18 years in doses up to 150 mg twice daily.

Effects on laboratory tests.

No data available.

4.5 Interactions with Other Medicines and Other Forms of 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 system 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) Competition for renal tubular secretion.

Since ranitidine is partially eliminated by the cationic system, it may affect the clearance of other drugs eliminated by this route. High doses of ranitidine (e.g. such as those used in the treatment of Zollinger-Ellison syndrome) may reduce the excretion of procainamide and N-acetylprocainamide resulting in increased plasma levels of these drugs.

3) Alteration of gastric pH.

The bioavailability of certain drugs may be affected. This can result in either an increase in absorption (e.g. triazolam, midazolam, glipizide) or a decrease in absorption (e.g. ketoconazole, atazanavir, delavirdine, gefitinib).
If high doses (2 g) of sucralfate are coadministered with ranitidine, the absorption of the latter may be reduced. This effect is not seen if sucralfate is taken after an interval of two hours.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

There are no data on the effects of ranitidine on human fertility. Reproduction studies performed in rats and rabbits have revealed no evidence of impaired fertility or harm to the foetus due to ranitidine.
(Category B1)
The safety of ranitidine in pregnancy has not been established. Ranitidine crosses the placenta. Zantac should only be used during pregnancy if considered essential. If the administration of Zantac is considered to be necessary, its use requires that the potential benefits be weighed against possible hazards to the patient and to the foetus.
Ranitidine is secreted in breast milk in lactating mothers but the clinical significance of this has not been fully evaluated. Zantac should only be used by nursing mothers if considered essential.

4.7 Effects on Ability to Drive and Use Machines

The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.

4.8 Adverse Effects (Undesirable Effects)

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at http://www.tga.gov.au/reporting-problems.
The following have been reported as events in clinical trials or in the routine management of patients treated with ranitidine. The relationship to ranitidine therapy has not been clear in many cases. Headache, sometimes severe, has been reported in a very small proportion of patients.

Central nervous system.

Rarely, malaise, dizziness, somnolence, insomnia and vertigo. Rare cases of reversible mental confusion, depression and hallucinations have been reported, predominantly in severely ill and elderly patients. In addition reversible involuntary movement disorders have been reported rarely. There have been a few reports of reversible blurred vision suggestive of a change in accommodation. Reversible impotence has been reported rarely.

Cardiovascular.

As with other H2-receptor antagonists, rare reports of tachycardia, bradycardia, premature ventricular beats, A-V block and asystole.

Gastrointestinal.

Constipation, diarrhoea, nausea/ vomiting, abdominal discomfort/ pain.

Hepatic.

Transient and reversible changes in liver function tests can occur. In normal volunteers, SGPT values were increased to at least twice the pretreatment levels in 6 of 12 subjects receiving 100 mg intravenously four times daily for 7 days, and in 4 of 24 subjects receiving 50 mg intravenously four times daily for 5 days. There have been occasional reports of hepatitis (hepatocellular or hepatocanalicular or mixed) with or without jaundice. These were usually reversible.

Musculoskeletal.

Rare reports of arthralgias and myalgia.

Haematologic.

Rare reports of agranulocytosis or pancytopenia, sometimes with marrow hypoplasia or aplasia, have been reported. Blood count changes (leucopenia, thrombocytopenia) have occurred in a few patients. These are usually reversible.

Endocrine.

Controlled studies in animals and man have shown no stimulation of any pituitary hormone by ranitidine, no antiandrogenic activity, and cimetidine induced gynaecomastia and impotence in hypersecretory patients have resolved when ranitidine was substituted. However, occasional cases of breast conditions such as gynaecomastia and galactorrhoea, impotence and loss of libido have been reported in male patients receiving ranitidine, but the incidence did not differ from that in the general population.

Integumental.

Rash, including rare cases of mild erythema multiforme. Rare cases of vasculitis and alopecia have been reported.

Renal.

Very rare cases of acute interstitial nephritis have been reported.

Other.

Rare cases of hypersensitivity reactions (e.g. fever, bronchospasm, anaphylactic shock, urticaria, angioneurotic oedema, hypotension, chest pain, rash, eosinophilia), small increases in serum creatinine. Acute pancreatitis has been reported rarely.

4.9 Overdose

There has been virtually no experience with overdosage with Zantac injection and limited experience with oral doses of ranitidine. Reported acute ingestions of up to 18 g orally have been associated with transient adverse effects similar to those encountered in normal clinical experience (see Section 4.8 Adverse Effects (Undesirable Effects)). In the case of the effervescent tablets, clinicians should be aware of the sodium content. Symptomatic and supportive therapy should be given as appropriate. If need be, the drug may be removed from the plasma by haemodialysis.
Zantac oral liquid contains approximately 7.5% w/v ethanol (alcohol), i.e. up to 375 mg per 5 mL spoonful (approximately a teaspoonful). This should be taken into account in children, pregnant or lactating women, or high risk groups (alcoholism, liver disease, epilepsy, brain injury or disease). It may modify or increase the effect of other medicines.
Rapid bolus injection of 300 mg intravenously (six times the recommended dose which should be given slowly) caused dizziness and peripheral vasodilatation.
For information on the management of overdose, contact the Poisons Information Centre on 131126 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Animal experiments both in vitro and in vivo have established that ranitidine is a selective, competitive antagonist of histamine at H2-receptor sites. Ranitidine has no significant interaction at histamine H1-receptors, muscarinic receptors or β-adrenoceptors. Ranitidine is a potent inhibitor of gastric secretion in the rat and dog.
All the evidence from human studies is compatible with a selective, competitive antagonism of histamine H2-receptors by ranitidine in man. Oral or intravenous administration of ranitidine inhibits both basal gastric secretions and gastric acid secretion induced by histamine, pentagastrin and other secretagogues. On a weight basis ranitidine is between 4 and 9 times more potent than cimetidine.
After oral administration of ranitidine, the plasma concentrations of ranitidine achieved are directly related to the dose administered. A plasma ranitidine concentration of 50-100 nanogram/mL has an inhibitory effect upon stimulated gastric acid secretion of approximately 50%.
Inhibition of pentagastrin induced gastric acid secretion increases with dose, being approximately 90% two hours after an oral 150 mg dose and a significant effect is still evident 12 hours after this dose. In 10 patients with duodenal ulcer, 150 mg ranitidine given orally every 12 hours significantly reduced mean 24 hour hydrogen ion activity by 69% and nocturnal gastric acid output by 90%, whereas cimetidine (200 mg three times daily and 400 mg at night) reduced mean 24 hour hydrogen ion activity by 48% and nocturnal gastric acid output by 70%.
Pepsin secretion is also inhibited by ranitidine, but secretion of gastric mucus is not affected. Ranitidine does not alter the secretion of bicarbonate or enzymes from the pancreas in response to secretin and pancreozymin. Reduction in gastric acid secretion induced by ranitidine 150 mg twice daily for 7 days did not cause bacterial overgrowth in the stomach.
Pulse rate, blood pressure, electrocardiogram and electroencephalogram were not significantly affected in man following recommended doses of ranitidine.
Chronic ranitidine therapy (300 mg/day for 28 days) had no effect on serum prolactin, gastrin, thyroid stimulating hormone, follicle stimulating hormone, luteinising hormone, gonadotrophins, testosterone, oestriol, progesterone or cortisol levels.
One study in 30 male duodenal ulcer patients showed a significant decrease in basal thyroxine levels after 4 weeks' treatment with 300 mg ranitidine daily, but no significant change in thyroid stimulating hormone was noted. Acute administration of 50 mg ranitidine intravenously had no effect on plasma aldosterone in healthy male volunteers whereas it caused a significant reduction in vasopressin. Cimetidine 200 mg intravenously had a similar effect on vasopressin.

Clinical trials.

No clinical trial data available.

5.2 Pharmacokinetic Properties

Absorption.

Peak plasma levels occur about 2-3 hours after oral administration of ranitidine. Absorption is not significantly altered by food or concurrent antacid administration.
Following oral administration of 150 mg ranitidine, maximum plasma concentrations (300 to 580 nanogram/mL) occurred after 1 to 3 hours. Two distinct peaks or a plateau in the absorption phase suggest reabsorption of drug secreted into the intestine. The absolute bioavailability of ranitidine is 50 to 60%, and plasma concentrations increase proportionally with increasing dose up to 200 mg. Bioavailability of ranitidine is approximately 50%. Serum protein binding of ranitidine in man is in the range 10-19%. The elimination half-life is approximately 2 hours.

Distribution.

Ranitidine is not extensively bound to plasma proteins (15%), but exhibits a large volume of distribution ranging from 96 to 142 L.

Metabolism.

The fraction of the dose recovered as metabolites is similar after both oral and intravenous dosing; and includes 6% of the dose in urine as the N-oxide, 2% as the S-oxide and small amounts of desmethylranitidine and the furoic acid analogue. The 24 hour urinary recovery of free ranitidine and its metabolites is about 40% after oral administration of the drug.

Excretion.

Plasma concentrations decline biexponentially, with a terminal half-life of 2 to 3 hours. The major route of elimination of unchanged ranitidine is renal. Renal clearance is approximately 500 mL/min, which exceeds glomerular filtration indicating net renal tubular secretion.

Patients over 50 years of age.

In patients over 50 years of age, half-life is prolonged (3 to 4 hours) and clearance is reduced, consistent with the age related decline of renal function. However, systemic exposure and accumulation are 50% higher. This difference exceeds the effect of declining renal function, and indicates increased bioavailability in older patients.
Impairment of renal function requires a reduction in dosage (see Section 4.4 Special Warnings and Precautions for Use). Impairment of liver function may increase the bioavailability of ranitidine but has no significant effect on the elimination half-life. However, in the presence of normal renal function, no dosage reduction for oral or intravenous ranitidine appears necessary in patients with hepatic impairment.

5.3 Preclinical Safety Data

Genotoxicity.

No data available.

Carcinogenicity.

No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Zantac 150 mg tablets contain the following excipients: magnesium stearate, microcrystalline cellulose and opadry white OY-S-7322 (PI 2450).
Zantac 300 mg tablets contain the following excipients: croscarmellose sodium, magnesium stearate, microcrystalline cellulose and opadry white OY-S-7322 (PI 2450).
Zantac 150 mg dispersible tablets contain the following excipients: croscarmellose sodium, hyprolose, hypromellose, magnesium stearate, microcrystalline cellulose, peppermint flavour 17.02.0608 (PI 868), saccharin sodium and titanium dioxide.
Zantac 150 mg effervescent tablets contain the following excipients: aspartame, grapefruit flavour No. 18C222 (17.01.9455) (PI 1815), monosodium dihydrogen citrate, orange flavour No.6 (15.02.1003) (PI 1816), povidone, sodium benzoate and sodium bicarbonate.
Zantac 300 mg effervescent tablets contain the following excipients: aspartame, grapefruit flavour No. 18C222 (17.01.9455) (PI 1815), monosodium dihydrogen citrate, orange flavour No.6 (15.02.1003) (PI 1816), povidone, sodium benzoate and sodium bicarbonate.
Zantac oral liquid contains the following excipients: butyl hydroxybenzoate, ethanol, hypromellose, mint flavour 17.42.3632 (PI 1255), monobasic potassium phosphate, propyl hydroxybenzoate, saccharin sodium, sodium chloride, dibasic sodium phosphate, sorbitol solution (70 per cent) (non-crystallising) and purified water.
Zantac injection contains the following excipients: monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate heptahydrate and water for injections.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Zantac 150 mg and 300 mg tablets and Zantac 150 mg dispersible tablets should be stored below 30°C, in a dry place.
Zantac 150 mg effervescent tablets and Zantac 300 mg effervescent tablets should be stored below 25°C. Protect from moisture.
Zantac oral liquid 150 mg/10 mL and Zantac injection 50 mg/2 mL should be stored below 25°C.

6.5 Nature and Contents of Container

Zantac 150 mg tablets are available in Al/Al foil blister packs of 2 (starter packs), 6, 60 and 90 tablets.
Zantac 300 mg tablets are available in Al/Al foil blister packs of 2 (starter packs), 4 and 30 tablets.
Zantac 150 mg dispersible tablets are available in foil strip packs of 10 and 60 tablets.
Zantac 150 mg effervescent tablets are available in polypropylene tubes in packs of 10, 30 or 60 tablets or in foil strip packs of 4 tablets.
Zantac 300 mg effervescent tablets are available in polypropylene tubes in packs of 15 or 30 tablets or in foil strip packs of 4 tablets.
Zantac oral liquid is available in 300 mL amber glass bottles.
Zantac injection is available in 2 mL ampoules in packs of 5. The injection is buffered with monobasic potassium acid phosphate 0.096% w/v and dibasic sodium phosphate 0.240% w/v to pH 7.
Note: Not all strengths, dose forms, pack sizes and container types are being distributed in Australia.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Ranitidine hydrochloride is a histamine H2-receptor antagonist. It is an aminoalkyl substituted furan and is structurally different from cimetidine lacking the imidazole ring and the cyanoguanidine group. Ranitidine hydrochloride is a white to pale yellow granular solid with a melting point of about 140°C. It is freely soluble in water, with a partition coefficient between n-octanol and water log P = 0.20. It has a slightly bitter taste and sulfur-like odour.
Molecular formula: C13H22N4O3S.HCl, molecular weight: 350.9, chemical name: N-(2-(((5-((Dimethylamino)methyl)-2-furan-yl)methyl)thio)ethyl)N'-methyl-2-nitro-1, 1-ethenediamine, hydrochloride.

Chemical structure.


CAS number.

66357-59-3.

7 Medicine Schedule (Poisons Standard)

S4.

Summary Table of Changes