Medication features:

  • Classified as H2 blockers
  • Fast relief against peptic ulcers and gastro-oesophageal reflux disease
  • Works by blocking the histamine found in the stomach


Available strengths:

150 mg


Price £16.99

Includes free private prescriptions

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Delivery Time


Expected delivery date:

Wednesday, 13 December 2023

If you order within:


Next Day Delivery

Next Day

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UK Registered Pharmacy

UK Registered

Discreet & Confidential

Discreet &

  • Overview
  • FAQ
  • Side Effects
  • Patient Information Leaflet
  • Reviews

What is Ranitidine

Ranitidine is intended to provide immediate relief from peptic ulcers, gastro-oesophageal reflux disease-causing heartburn, chronic indigestion, and ulcers that form due to the use of non-steroidal anti-inflammatory medications such as diclofenac.

How effective Is Ranitidine?

Ranitidine is an effective way of managing and controlling symptoms such as heartburn, indigestions and stomach ulcers. It is a fast-acting treatment that offers relief within one or two hours upon ingestion. The effect lasts for 12 hours, but you are advised to follow the doctor's instructions since this is a prescription-only medication. Ranitidine takes a few weeks to work effectively.

How does Ranitidine work?

Ranitidine belongs to a class of medications known as H2 receptors. It works by blocking the H2 receptors – found in the stomach lining - from producing excess stomach acid, thus addressing symptoms such as acid aspiration during labour, or surgery, recurrent bleeding from peptic ulcers and bleeding from stress ulceration in people who are critically ill.

Ranitidine tames the backflow of acid into the oesophagus preventing heartburn symptoms and damage to the oesophagus. It also reduces the amount of stomach acid that flows into the duodenum allowing peptic ulcers to heal and preventing recurrent bleeding.


Can I buy Ranitidine online?

Ranitidine requires a prescription, although you are very welcome to book an appointment with a health expert at Click Pharmacy to discuss how best to use this product.

Given that you have a prescription, you can buy this medication online in the quantity and strength that is recommended by your doctor. 

Ranitidine is available in the 75mg (doesn’t require a prescription), 150mg and 300mg tablets. Therefore once you purchase any of these units, they will be sent directly to you by Next Day Delivery.

What dose should I choose?

Ranitidine is available in different strengths, and only Ranitidine 75mg is available over the counter without a prescription. It is suitable for persons over 16 years and adults.

Otherwise, other Ranitidine treatments require a prescription, and the dosage should be taken as per the doctor's instructions.

How should I take Ranitidine

Follow the doctor’s prescription while taking this medicine.  Swallow each tablet whole and with water. 

Usually, the dose prescribed will depend on your condition. From children over the age of 12 years to adults, the prescribed dose is 150 mg twice a day, in the morning/evening, or 300 mg at bedtime.

The doctor works out the right dosage based on your prescription.

Nevertheless, do not forget to read instructions for best use.

How long do I take Ranitidine for before I notice a difference?

Ranitidine is a fast-acting treatment against recurrent stomach and intestine ulcers. Upon taking the medication, you will feel relieved within one or two hours. Its efficacy lasts within 12 hours, although for effective use, you are advised to keep following the doctor’s prescription. This is because it may take a few weeks for Ranitidine to eradicate all the acid issues, a factor that depends on the level of your symptoms and the strength of the prescribed medication.

Ranitidine is available in different strength variations, including 75mg, 150mg and 300mg tablets, liquid, effervescent tablets of 150mg and 300mg strengths, and as an injection given at the hospital. 

Of the above, only Ranitidine 75mg is available over the counter without a prescription. It is suitable for persons over 16 years and adults.

Always check the label and read instructions before use to get the best out of this medication.

What are the side effects of Ranitidine?

The main side effect of using this medication may be a stomach upset or diarrhoea, as Ranitidine contains castor oil.

However, if you notice side effects such as itching or hives on the skin, swelling of the lips, face, tongue or any other parts of the body, shortness of breath, wheezing, chest pains, trouble breathing, fever or feeling weak when standing up, notify your doctor immediately. These are all signs of an adverse reaction towards the medicine, and you may be allergic to the ingredients in the product. 

This medication may also affect your kidneys by changing the amount and colour of the water you pass. This could lead to pain when passing urine, blood in urine, fever, back pain and changes in blood tests. 

In the same way, Ranitidine may cause side effects such as severe stomach pain (pancreatitis), slow or irregular heartbeat, stomach pain, nausea, constipation, skin rash, changes to liver functions and other rare side effects that maybe detected in blood tests.

Therefore if ever you experience any of the listed side effects, including those not indicated on your leaflet, seek immediate help from your GP or hospital. 

You are also welcome to consult our specialists at Click Pharmacy should you require any further advice.

When shouldn’t I take Ranitidine?

Do not begin this treatment if you are hypersensitive towards any of the listed ingredients on the product. 

Once you notice any of the side effects indicated on the leaflet, including those not mentioned, do not continue with the treatment. Report this to your doctor immediately. 

Also, inform your doctor if you already on other medication before taking Ranitidine. This is because Ranitidine can affect the way different drugs interact and vice versa. Particularly if these medications include NSAID medicines such as ibuprofen, naproxen, aspirin, or a local anaesthetic such as lidocaine. 

Other drugs you shouldn't take whilst taking Ranitidine include diazepam, heart problem drugs such as propranolol and procainamide, drugs that address breathing problems such as theophylline, phenytoin for epilepsy, warfarin, atazanavir, glipizide, triazolam, gefitinib, sucralfate (for duodenal ulcers) or ketoconazole. 

If you are about to undergo surgery, and yet you're under Ranitidine treatment, inform your doctor before the operation. This is to avoid a bad reaction with midazolam which is a medication given to a patient before an operation. 

Overall, the best thing is to talk to your doctor if you are unsure whether or not you should take Ranitidine. Especially if you are pregnant, planning to get pregnant or are currently breastfeeding.

What is the difference between Ranitidine and Zantac/Prilosec?

Ranitidine is a generic drug and is available in different brand name commonly known as Zantac. Ranitidine and Zantac work in the same way by blocking H2 receptors from producing excessive acid. This action treats indigestion, heartburns, stomach ulcers and prevents acid reflux and bleeding caused excess stomach acid. 

On the other hand, Prilosec is a brand name for a generic treatment known as Omeprazole. It is also known as proton pump inhibitor and works by blocking the pumps in your gut that produce acid.

All of the above treatments are prescription-only medications, except Ranitidine 75mg tablets.

Can I take Ranitidine after food?

Yes, you can take Ranitidine after food. However, taking the medicine 30 to 60 minutes before consuming foods or drinks that trigger your symptoms is strongly recommended.

Ranitidine Alternatives

You can find a number of prescription and non-prescription (OTC) treatments to treat symptoms of acid reflux. Common prescription-based alternative treatments include:

  • Lansoprazole
  • Omeprazole
  • Rabeprazole

Additionally, you can find over-the-counter treatments for acid reflux, too. You can get them without a prescription at any local pharmacy. These treatments include

  • Rennie
  • Gaviscon
  • Alka Seltzer
  • Peptac

How long can I take Ranitidine for?

You can take Ranitidine for a limited time. However, it is not suitable for long-term use. In fact, experts advise using the treatment for two weeks only.

If you still experience severe symptoms following the two-week point, you should consult your GP as soon as possible.

Can I take an Antacid and Ranitidine together?

No, avoid combining treatments. If you take Antacid and Ranitidine at the same time, then the absorption may be affected greatly. This can lead to complications with the efficacy of the treatments, particularly Ranitidine. If you wish to use the two medicines, you should wait an hour or two before using the second treatment.

Who is not suitable for Ranitidine?

Ranitidine is not suitable for everyone. The efficacy may vary from person to person, too. However, seek medical attention right away if you experience any of the following symptoms:

  • Unintended weight loss or weight fluctuations
  • Vomiting or nausea
  • Blood in your vomit
  • Dark or bloody stools

Are there any drugs which might interact with Ranitidine?

It would be best if you informed your GP about the current medications you are on, as many medicines tend to interact with Ranitidine. As a result, they could affect the efficacy of the treatment or even render it useless. In addition to this, Ranitidine may lead to a significant decrease or an increase in the levels of drugs present in your bloodstream.

Ranitidine’s efficacy may be decreased by the following:

  • Ketoconazole
  • Atazanavir
  • Delavirdine
  • Gefitinib
  • Sucralfate

Ranitidine may amplify the efficacy of the following:

  • Procainamide
  • N-acetyl procainamide
  • Triazolam
  • Midazolam
  • Glipizide

What if I forget to take my dose of Ranitidine Tablets?

If you forget to take your dose of Ranitidine Tablets you should take it as soon as you remember unless it is almost time for your next dose. If it is almost time for your next dose you should skip the dose you just missed and continue as normal. You should never take two doses at once, even if you are making up for a missed dose.

Can pregnant or breastfeeding women use Ranitidine Tablets?

Although it is generally safe for pregnant and breastfeeding women to use Ranitidine Tablets. It is advised to consult with a professional such as a Gp, pharmacist or midwife before taking them. This is to ensure the medicine does not cause any harm to both born and unborn babies.

Can I drink alcohol while using Ranitidine Tablets?

Although drinking alcohol does not interfere with Ranitidine Tablets itself, it does cause the stomach to produce more acid. It is advised to avoid drinking excessive amounts of alcohol for the duration of your treatment.

Like all medicines, after using Ranitidine Tablets you are likely to experience a number of side effects. Common side effects and how to overcome them include the following:

  • Stomach pains: rest and eat smaller, more frequent meals
  • Constipation: increase your intake of fibre high foods such as fruits, vegetables, cereal and legumes.
  • Feeling sick: avoid eating large rich and spicy meals

If any of these side effects worsen, you should stop using Ranitidine Tablets immediately and seek medical advice from a GP or pharmacist as soon as possible.

Always read the patient information leaflet before starting your treatment. The patient information can be found here.

Authored by

Last reviewed 11 April 2023

Superintendent Pharmacist GPhC No.2220953

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