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Terms Of Use


Brand Name(s) : Gavilast, Gavilast-p, Histac, Pylorid, Ranitic, Ranitil, Ranzac, Zantac, Zantac 75, Zantac 75 dissolve, Zantac 75 relief, Zantac 75 relief (dissolve)
Side Effects


Ranitidine should be used with caution in:

  • Elderly
  • Pregnancy
  • Breast feeding
  • Stomach cancer
  • Kidney disease
  • Taking non-steroidal anti-inflammatory drugs
  • Lung disease
  • Diabetes
  • Problems with your immune system
  • Acute porphyria (a rare metabolic disorder)

It should not be used in:

  • Allergy to ranitidine or any of the other components of the medicine

Also see list of precautions and interactions


Store below 25°C in the original packaging.


What is it used for?

  • Ranitidine is used to treat a number of problems caused by stomach acid.
  • It is an H2-receptor antagonist, also know as an H2 blocker or H2 histamine blocker.
  • It is used to reduce the amount of acid produced in the stomach.
  • In general this drug is used in problems caused by stomach acid, including treating stomach ulcers and preventing ulcers from forming in the stomach or the part of the gut just beyond the stomach (the duodenum). It is used to prevent the discomfort of heartburn, caused by acid flowing back up from the stomach into the gullet (oesophagus), also know as acid reflux. It is also used to prevent stomach acid from entering the gullet when you are under an anaesthetic (for an operation).
  • Benefits of being on this drug can include prevention of stomach and duodenal ulcers and relief from the pain and discomfort caused by stomach ulcers, bleeding stomach ulcers, and heartburn or acid reflux.

Listed below are the typical uses of ranitidine.

  • To treat stomach and duodenal ulcers
  • To protect against stomach and duodenal ulcers
  • To treat problems caused by acid in the gullet, a type of heartburn
  • To prevent ulcers from bleeding
  • Before surgical operations, to prevent acid coming up from the stomach during the anaesthetic.
  • Zollinger-Ellison syndrome (a disorder where increased levels of the hormone gastrin are produced, causing the stomach to produce too much acid).

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.

  • When taken with antibiotic medicines, ranitidine is used to help clear up bacterial infections in the stomach caused by Helicobacter pylori, which cause stomach ulcers.


How often do I take it?

  • Take this medication by mouth usually 1 to 4 times daily, with water. Take these tablets exactly as instructed by your doctor.
  • When given intravenously or intramuscularly, your injection will be administered by your doctor or another health care professional.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take up to a few days before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • There is no need to avoid certain foods or alcohol because you are taking ranitidine. You may be recommended to avoid certain foods or alcohol because of your condition. Ranitidine does not affect your ability to drive or operate machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


  • Headache
  • Dizziness
  • Diarrhoea
If any of these persist or you consider them severe then inform doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms:

  • Allergic reaction, including rash or itching, swelling of your face, lips, tongue or other parts of your body, trouble breathing
  • Kidney problems, symptoms might include back pain, fever, pain when passing urine, blood in the urine
  • Severe stomach pain
  • A slow or irregular heartbeat

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking ranitidine, tell your doctor or pharmacist if you are allergic to it; or to other H2 receptor antagonists; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: allergy to ranitidine or any of the other components of the medicine.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: pregnancy, breast feeding, stomach cancer, kidney disease, taking non-steroidal anti-inflammatory drugs (such as ibuprofen), lung disease, diabetes, problems with your immune system, acute porphyria (a rare metabolic disorder).

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol intake is not known to affect ranitidine.

The elderly: ranitidine should be used with caution in the elderly as it may increase your risk of developing pneumonia.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Ranitidine is not recommended to take if you are, or are planning to become, pregnant.

First trimester: avoid unless essential, but not known to be harmful
Second trimester: avoid unless essential, but not known to be harmful
Third trimester: avoid unless essential, but not known to be harmful

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


A significant amount of ranitidine passes into breast-milk, and should not be used while breastfeeding unless considered essential.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

There are medicines that are known to interact with ranitidine and your doctor may well have considered this, however if you are taking any of the following medicines please make sure your doctor or pharmacist is aware of this. Do not start, stop or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • None known.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • Non-steroidal anti-inflammatory (NSAID) medicines (used for pain relief and to reduce inflammation)
  • Lidocaine, a local anaesthetic
  • Propranolol, procainamide or n-acetylprocainamide (used for heart problems)
  • Diazepam and midazolam (sedatives used to treat anxiety and other conditions)
  • Phenytoin (used in epilepsy)
  • Theophylline (used in asthma)
  • Warfarin (used to thin your blood)
  • Glipizide (which lowers blood glucose)
  • Atazanavir or delaviridine (used to treat HIV infection)
  • Triazolam (used for difficulty sleeping)
  • Gefitinib (used to treat lung cancer)
  • Ulipristal
  • Ketoconazole (an antifungal medicine)

This information does not contain all possible interactions. Therefore, before using ranitidine, tell your doctor or pharmacist of all the products you use.


If you think you, or someone you care for, might have accidentally taken more than the recommended dose of ranitidine or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited or TicTac Communications Ltd. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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