Description: Ranitidine is an H2-receptors blocker that stops gastric acid secretion and reduces the amount of acid produced by the stomach.


Absorption: Readily absorbed from the GI tract. Bioavailability: Approx 50%. Time to peak plasma concentration: Approx 2-3 hr (oral); approx 15 min (IM).

Distribution: Widely distributed; enters breast milk, crosses the placental barrier. Volume of distribution: Approx 1.4 L/kg. Plasma protein binding: Approx 15%.

Metabolism: Hepatically metabolised. Small portion is converted to N-oxide (major metabolite, approx 4-6% of a dose), S-oxide and desmethylranitidine.

Excretion: Via urine (oral: Approx 30%, IV: 70%) as unchanged drug and in the faeces. Elimination half-life: Approx 2-3 hr.

Ranitidine is used to treat ulcers of the stomach and intestines and prevent them from coming back after they have healed. This medication is also used to treat certain stomach and throat (esophagus) problems (such as erosive esophagitis, gastroesophageal reflux disease-GERD, Zollinger-Ellison syndrome). It relieves symptoms such as cough that doesn’t go away, stomach pain, heartburn, and difficulty swallowing. Ranitidine belongs to a class of drugs known as H2 blockers.

How to use ranitidine:

Take this medication by mouth with or without food as directed by your doctor, usually once or twice daily. It may be prescribed 4 times a day for some conditions. If you are taking this medication once daily, it is usually taken after the evening meal or before bedtime.

The dosage and length of treatment are based on your medical condition and response to therapy. In children, dosage may also be based on body weight. Follow your doctor’s instructions carefully. You may take other medications (e.g., antacids) for your condition as recommended by your doctor.

Take this medication regularly in order to get the most benefit from it. To help you remember, take it at the same time(s) each day. Do not increase your dose or take it more often than prescribed. Do not stop taking this without your doctor’s approval because this may delay healing of the ulcer.

Tell your doctor if your condition does not improve or if it worsens.

Headache, constipation or diarrhea may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

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.

Tell your doctor right away if you have any serious side effects, including:

  • blurred vision,
  • mental/mood changes (e.g., agitation, confusion, depression, hallucinations),
  • easy bleeding/bruising,
  • enlarged breasts,
  • severe tiredness,
  • fast/slow/irregular heartbeat,
  • signs of infection (such as sore throat that doesn’t go away, fever, chills),
  • severe stomach/abdominal pain,
  • dark urine,
  • yellowing skin/eyes.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe 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.


Before taking ranitidine, tell your doctor or pharmacist if you are allergic to it; or to other H2 blockers (e.g., cimetidine, famotidine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: a certain blood disorder (porphyria), immune system problems, kidney problems, liver problems, lung diseases (e.g., asthma, chronic obstructive pulmonary disease-COPD), other stomach problems (e.g., tumors).

Some symptoms may actually be signs of a more serious condition. Get medical help right away if you have: heartburn with lightheadedness/sweating/dizziness, chest/jaw/arm/shoulder pain (especially with shortness of breath, unusual sweating), unexplained weight loss.

Older adults may be more sensitive to the side effects of this drug, especially confusion.

Ranitidine should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

Ranitidine passes into breast milk. Consult your doctor before breast-feeding.


Some products need stomach acid so that the body can absorb them properly. Ranitidine decreases stomach acid, so it may change how well these products work. Some affected products include atazanavir, dasatinib, delavirdine, certain azole antifungals (such as itraconazole, ketoconazole), pazopanib, among others.

Do not use this medication with other products that contain ranitidine or other H2 blockers (cimetidine, famotidine, nizatidine).

This medication may interfere with certain laboratory tests (including certain urine protein tests), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.


If overdose is suspected, contact a poison control center or emergency room right away.


Do not share this medication with others.

Lifestyle changes such as stress reduction programs, stopping smoking, limiting alcohol, and diet changes (such as avoiding caffeine and certain spices) may help this medication work better. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

Laboratory and/or medical tests (e.g., endoscopy, kidney function tests) may be performed to monitor your progress or check for side effects. Consult your doctor for more details.

Missed Dose

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.


Store in a tightly closed container at room temperature between 59-86 degrees F (15-30 degrees C) away from moisture and light. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.


Available Brands

  • Aciloc [ Cadila Pharma ]
  • Aglotac [ Tianjin Pharma ]
  • Boie Ranitidine [ Boie ]
  • Contracid [ Umedica ]
  • Entac Ampoule [ Neon ]
  • Loracid [ Medica Korea ]
  • Pep-Bloc [ PT Sanbe Farma ]
  • Peptica [ Littman ]
  • Phil Pharmawealth/Atlantic Ranitidine [ Atlantic Lab ]
  • Ranivex [ Yanzhou Xier Kangtai ]
  • Raxide [ GXI ]
  • RiteMED Ranitidine [ RiteMED ]
  • Ulcemed [ Medica Korea ]
  • Ulcepac [ Biolink Pharma ]
  • Ulcin [ Biolab ]
  • Ulzim [ Medhaus ]
  • Vidadine [ Scott-Edil Pharmacia ]
  • Zantac/Zantac 75 [ GlaxoSmithKline ]
  • Zeptag [ Bosch ]

Also marketed as

  • Aceptin [ Metro Pharma ]
  • Aciran [ Sel-J Pharma ]
  • Alisazim [ Sel-J Pharma ]
  • Ameket [ SM Pharma ]
  • Ceranid [ Sandoz ]
  • Clodine [ Mount Mettur ]
  • Dalycrid [ Pasteur Pharma ]
  • Danitin [ Yung Shin ]
  • Dart [ Medicaids ]
  • Diranite [ Caplin ]
  • Duopharma Ranitidine Hydrochloride [ Duopharma (M) Sdn Bhd ]
  • Dynastin [ Yung Shin ]
  • Entac Tablet [ Elin ]
  • Equaline [ Umedica ]
  • Eu-Ran [ EuroHealth Care ]
  • Gastrone [ Crisdy-Na ]
  • Incid [ Verheilen ]
  • Increph [ Sel-J Pharma ]
  • Intac [ Coral ]
  • Microtec [ Sel-J Pharma ]
  • Mordek [ Vitalink ]
  • Normaxid [ Stallion Labs ]
  • Pharex Ranitidine [ PPC ]
  • RA Bloc [ Euro-Med ]
  • Radine [ Korea United Pharma ]
  • Ramadine [ PT Indofarma ]
  • Ranae [ Umedica ]
  • Randin [ Pasteur Pharma ]
  • Ranidex [ PSA ]
  • Ranifin [ Vhermann Pharma ]
  • Ranimed [ D. B. Manix ]
  • Ranisan [ Kopran ]
  • Ranitab [ Sel-J Pharma ]
  • Ranitac [ Sinochem Ningbo ]
  • Ranitalis [ Pan-Ject Pharma ]
  • Ranitein [ Steinbach ]
  • Ranivint [ Sel-J Pharma ]
  • Rantizec [ Ildong Pharm ]
  • Rapidin [ Danlex ]
  • Renfort [ Pasteur Pharma ]
  • Rentsan [ Pharmasan ]
  • Ulcedrug [ EuroHealth Care ]
  • Ulceral [ Vamsler ]
  • Ulceran [ D. B. Manix ]
  • Ulcergo [ ACME ]
  • Ulcergo 300 [ ACME ]
  • Ulcerix [ Oboi ]
  • Ulci-Bloc [ Bal Pharma ]
  • Ulci-Cure [ Sel-J Pharma ]
  • Ulran 150 [ Pasteur Pharma ]
  • Zanitine [ Lloyd ]
  • Zantol [ Zhejiang Ruixin ]
  • Zeltac [ Sel-J Pharma ]
  • Zerdin [ Genesis ]
  • Zidaxim [ Flamingo ]

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