Zantac
Generic name: ranitidine
Pharmacist-reviewed drug information from the RxWiki encyclopedia.
Overview
Zantac is both an over-the-counter and a prescription medication used to treat conditions of the stomach, esophagus, and intestines. The over-the-counter (OTC) form is used to treat heartburn, acid indigestion, and sour or upset stomach. The prescription form is used to treat ulcers, GERD, erosive esophagitis, and other conditions.
Zantac belongs to a group of drugs called H2 blockers. It works by decreasing the amount of acid produced in the stomach.
This medication comes in regular tablet and syrup forms. Zantac is taken by mouth, up to 4 times a day. This medication is also available in an injectable form to be given directly into a vein (IV) or muscle (IM) by a healthcare professional.
Zantac over-the-counter (OTC) comes in tablet form and can be taken up to twice a day. Do not chew tablets.
Common side effects include headache, diarrhea, and constipation. Zantac can cause dizziness and drowsiness. Do not drive or operate machinery until you know how Zantac affects you.
What is it used for?
Zantac is used to treat:
- heartburn, acid indigestion, and sour or upset stomach
- ulcers
- gastroesophageal reflux disease (GERD) and erosive esophagitis. Both of these conditions result from stomach acid damaging the esophagus.
- conditions in which the stomach makes too much acid, such as Zollinger-Ellison syndrome
This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.
How to take it
Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.
The dose your doctor recommends may be based on the following:
- the condition being treated
- other medical conditions you have
- other medications you are taking
- how you respond to this medication
- your weight
- your height
- your age
- your gender
Injectable:
- Into the muscle (IM) Injection: 50 mg every 6 to 8 hours
- Into the vein (IV) Intravenous Injection:
- Intermittent Bolus: 50 mg (2 mL) every 6 to 8 hours
- IIntermittent Infusion: 50 mg (2 mL) every 6 to 8 hours
- Continuous Infusion: Deliver at a rate of 6.25 mg/hour
- For treatment of Zollinger-Ellison: Start the infusion at a rate of 1 mg/kg per hour.
Oral-Prescription
- Adult Use
- Active Duodenal Ulcer - The current recommended adult oral dosage of Zantac for duodenal ulcer is 150 mg of Zantac
twice daily. An alternative dosage of 300 mg of syrup once daily after the evening meal or at bedtime. - Maintenance of Healing of Duodenal Ulcers - The current recommended adult oral dosage is 150 mg at bedtime.
- Pathological Hypersecretory Conditions (such as Zollinger-Ellison syndrome) - The current recommended adult oral dosage is 150 mg twice daily. In some patients it may be necessary to administer Zantac 150-mg doses more frequently. Dosages up to 6 grams/day have been employed in patients with severe disease.
- Benign Gastric Ulcer - The current recommended adult oral dosage is 150 mg twice daily.
- Maintenance of Healing of Gastric Ulcers - The current recommended adult oral dosage is 150 mg at bedtime.
- GERD - The current recommended adult oral dosage is 150 mg twice daily.
- Erosive Esophagitis - The current recommended adult oral dosage is 150 mg 4 times daily.
- Maintenance of Healing of Erosive Esophagitis - The current recommended adult oral dosage is 150 mg twice daily.
- Active Duodenal Ulcer - The current recommended adult oral dosage of Zantac for duodenal ulcer is 150 mg of Zantac
- Pediatric Use
- Treatment of Duodenal and Gastric Ulcers - The recommended oral dose for the treatment of active duodenal and gastric ulcers is 2 to 4 mg/kg twice daily to a maximum of 300 mg/day.
- Maintenance of Healing of Duodenal and Gastric Ulcers - The recommended oral dose for the maintenance of healing of duodenal and gastric ulcers is 2 to 4 mg/kg once daily to a maximum of 150 mg/day.
- Treatment of GERD and Erosive Esophagitis - Published literature supports a dosage of 5 to 10 mg/kg/day, usually given as 2 divided doses.
Oral- Over-the-counter (OTC)
- To prevent symptoms- the recommended dose is 1 tablet, with a glass of water, 30 to 60 minutes before eating food or drinking beverages that cause heartburn. Can be used up to twice daily.
- To relieve heartburn associated with acid indigestion and sour stomach- the recommended dose is 1 tablet with a glass of water. Can be used up to twice daily.
Warnings
Serious side effects have been reported with Zantac including:
- Zantac is cleared from the body by the kidneys and liver. Talk to your doctor if you have kidney or liver disease.
- This medication can cause porphyria attacks in people with acute porphyria, a rare, inherited condition usually affecting the skin or nervous system. Do not take Zantac if you have a history of acute porphyria (a disease affecting heme in red blood cells).
- Hypersensitivity reaction: An allergic reaction to Zantac is possible. Call your doctor if you experience one or more of the following symptoms of a hypersensitivity reaction:
- difficulty swallowing or breathing
- hoarseness
- fever
- rash
- swelling
Do not take Zantac if you are allergic to the active ingredient, ranitidine.
If you are taking Over-the-counter Zantac, do not use if:
- if you have trouble or pain swallowing food, vomiting with blood, or bloody or black stools. These may be signs of a serious condition. See your doctor.
- with other acid reducers
- Stop Use and ask a doctor if:
- your heartburn continues or worsens
- you need to take this product for more than 14 days
Zantac can cause dizziness and drowsiness. Do not drive or operate machinery until you know how Zantac affects you.
Side effects
Serious side effects have been reported with Zantac. See “Drug Precautions” section.
Common side effects of Zantac include:
- headache
- constipation
- diarrhea
- nausea
- vomiting
- stomach pain
- dizziness
- fatigue
This is not a complete list of Zantac side effects. Ask your doctor or pharmacist for more information.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Drug interactions
Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:
- procainamide
- warfarin (Coumadin)
- triazolam (Halcion)
- midazolam
- glipizide (Glucotrol)
- ketoconazole (Nizoral)
- atazanavir (Reyataz)
- delavirdine (Rescriptor)
- gefitinib (Iressa)
This is not a complete list of Zantac drug interactions. Ask your doctor or pharmacist for more information.
Pregnancy
Tell your doctor if you are pregnant or plan to become pregnant.
The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.
Zantac falls into category B. Studies in animals have failed to demonstrate a risk to the unborn baby, and there are no well-controlled studies in pregnant women.
Breastfeeding
Tell your doctor if you are breastfeeding or plan to breastfeed. The active ingredient in Zantac is excreted in human breast milk. The effect of Zantac on the nursing infant is not known.
Quick facts
Ranitidine is usually taken 30 to 60 minutes before food that may cause heartburn.
The effervescent tablets should be dissolved in a glass of water before use.
Ranitidine can cause dizziness and drowsiness. Do not drive or operate machinery until you know how ranitidine affects you.
If ranitidine does not help your heartburn, talk to your doctor.
All information on this site is provided “as-is” for informational purposes only and is not a substitute for medical advice or treatment. You should consult with a medical professional if you have any questions about your health.