Zantac contains a medicine called ranitidine. This belongs to a group of medicines called H2-receptor antagonists. It lowers the amount of acid in your stomach.

Zantac (Ranitidine) Tablets

Zantac (Ranitidine) Tablets 150mg

includes free private prescription

Zantac (Ranitidine) Tablets 300mg

includes free private prescription


For adults (including the elderly) Zantac is used to:

  • heal and stop ulcers in the stomach, or the part of the gut it empties into (the duodenum)
  • help clear up infection in your stomach, when taken with antibiotic medicines (medicines taken to treat germs)
  • stop stomach ulcers when they are a side effect of some medicines
  • stop ulcers from bleeding
  • improve problems caused by acid in the food pipe (oesophagus) or too much acid in the stomach. Both of these can cause pain or discomfort sometimes known as ‘indigestion’, ‘dyspepsia’ or ‘heartburn’
  • stop acid coming up from the stomach while under anaesthetic during an operation.

Taking this medicine

  • Take this medicine by mouth.
  • Swallow each tablet whole with a glass of water.

Stop taking Zantac and see a doctor straight away, if you notice any of the following serious side effects, you may need urgent medical treatment:

  • allergic reactions, the signs may include:
    • rash, itching or hives on the skin
    • swelling of your face, lips, tongue or other parts of the body
    • chest pain, shortness of breath, wheezing or having trouble breathing
    • unexplained fever and feeling faint, especially when standing up
  • kidney problems, which can lead to back pain, fever, pain when passing urine, blood in the urine and changes in blood tests
  • severe stomach pain, this may be a sign of something called ‘pancreatitis’
  • a slow or irregular heartbeat

Check with your doctor or pharmacist before taking your medicine if:

  • you have stomach cancer
  • you have kidney problems. You will need to take a different amount of Zantac
  • you have had stomach ulcers before and you are taking Non-Steroidal Anti-Inflammatory (NSAID) medicines
  • you have a rare condition called acute porphyria
  • you are over 65 years old
  • you have lung disease
  • you are diabetic
  • you have any problems with your immune system.

If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before using this medicine.

Medical Advice

Please refer to the articles below to find out more information, medical guidance and advice from our doctors on how to best treat the condition.
Learn about available treatments, symptoms, side effects and what you can do to prevent it.

Symptoms of Acid Reflux
Acid reflux is a fairly common condition whereby the contents of the stomach acid and other stomach content rise back up into the oesophagus…
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Causes of Acid Reflux
It is now known that stomach acid is not actually the root cause of acid reflux. The main cause of heartburn and GORD is acid entering the oesophagus…
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