Zantac (ranitidine)

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Brand Name

Zantac {Boehringer Ingelheim Pharmaceuticals, Inc}

Generic Name

ranitidine, pronounced ra NI ti deen


What is Zantac?

Zantac is a medication that will help to decrease the amount of acid produced in your stomach. Belonging to a group of medications called histamine-2 blockers, Zantac is used to treat and prevent ulcers in your stomach and intestines. Patients with symptoms of gastroesophageal reflux disease, which is also known as GERD, as well as people with Zollinger-Ellison syndrome., which is when your stomach produces too much acid, may also be prescribed Zantac. Zantac may also be used for other purposes not listed in this medication guide.


Key Facts About Zantac

Zantac should not be used for an immediate relief of your heartburn symptoms. Sometimes heartburn may be confused with initial symptoms of a heart attack. You should seek emergency medical assistance if you experience chest pain or a heavy feeling, nausea, sweating, pain spreading to your arm or shoulder, or a general feeling of being ill.

Zantac is in FDA pregnancy category B. Tell your doctor if you are pregnant or plan to become pregnant while you are being treated with Zantac. We know that Zantac passes into breast milk and may harm a nursing baby. You should not use Zantac without telling your doctor if you are breastfeeding.

You may have an increased risk of developing pneumonia while taking Zantac. . Symptoms of pneumonia include chest pain, fever, shortness of breath, and coughing up green or yellow mucus. Tell your doctor if you are concerned about pneumonia.

You may need to take Zantac for up to 8 weeks before your ulcer heals. Continue taking this medication as your doctor has directed. Let your doctor know if you have not experienced any relief by the sixth week of treatment with Zantac.

Alcohol consumption may increase your risk of damage to your stomach while you are taking Zantac.


Before You Take Zantac

You should not take Zantac if you are allergic to ranitidine.

Tell your doctor if you have Zantac phenylketonuria, also known as PKU. The Zantac effervescent tablet may contain phenylalanine.

Let your doctor know if you have kidney disease, liver disease or porphyria before starting treatment with Zantac.

Before you start taking Zantac tell your doctor if you are taking triazolam (Halcion). You may not be able to use Zantac if this is the case, or you may need dosage adjustments and special tests while you are being treated with Zantac.


Zantac Drug Interactions

You should inform your doctor if you are taking any of the following:

  • Atazanavir
  • Delavirdine
  • Gefitinib
  • Glipizide
  • Ketoconazole
  • Midazolam
  • Triazolam
  • Warfarin

Other drugs you take that are not listed may interact with Zantac. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Zantac

Take Zantac exactly as prescribed by your doctor. Do not take Zantac in larger or smaller amounts, or for shorter or longer than recommended. Follow the directions on your prescription label.

You may need an antacid in addition to taking Zantac. Your doctor will recommend an antacid to help relieve your pain if needed. Do not take any antacids without talking to your doctor first. Follow your doctor’s directions about the type of antacid to use, how to use it and when to use it.

Do not break, chew or crush the Zantac effervescent tablet, and do not allow it to dissolve on your tongue. The 25 mg effervescent tablet needs to be dissolved in at least 1 teaspoon of water before swallowing it. The150 mg effervescent tablet should be dissolved in approximately 6 to 8 ounces of water.

Children who receive Zantac may be administered this medication via a medicine dropper. After dissolving your child’s dose of Zantac in the appropriate amount of liquid you can draw the liquid mixture into a medicine dropper and empty the dropper into your child’s mouth.

You must mix Zantac granules with 6 to 8 ounces of water before drinking it.

Use a special dose-measuring spoon or cup to administer Zantac liquid. Do not use a regular table spoon. If you do not have a dose-measuring device your pharmacist can give one to you.

Be aware that Zantac may cause unusual results with certain medical tests. Tell any doctor who treats you that you are taking Zantac.

Zantac should be stored at room temperature, and away from both moisture and heat.

If you miss a dose of Zantac you should attempt to take the missed dose as soon as you remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose.


Zantac Side Effects

If you experience any of the following adverse effects you should stop taking Zantac and seek emergency medical help immediately:

  • allergic reaction including breathing difficulties, hives, and swelling of your mouth, nose or throat
  • chest pain
  • clay colored stools
  • coughing up green or yellow mucus
  • easy bruising or bleeding
  • feeling short of breath
  • fever
  • heart rate that is uneven, either too fast or too slow
  • jaundice or yellowing of the skin or eyes
  • loss of appetite
  • nausea
  • problems with your vision
  • sore throat and headache with a severe blistering, peeling, and red skin rash alongside a fever
  • stomach pain
  • urine which is dark

Less serious side effects of Zantac may include:

  • constipation
  • decreased sex drive
  • diarrhea
  • dizziness
  • drowsiness
  • severe headache
  • impotence
  • insomnia and sleep problems
  • stomach pain
  • swollen or tender breasts (in men)
  • vomiting

It should be noted that this is not a complete list of possible side effects of Zantac. You should contact your physician for a complete list and medical advice regarding these effects.


Zantac Description and Dosing

Zantac is available in the U.S. in tablet, effervescent tablet and syrup dosage forms. Zantac tablets are available in both 150 mg and 300 mg doses. Efferdose tablets are offered in a 25 mg dosage. Zantac is also available in syrup form.

Dosages of Zantac will vary based on each individual patient. Your doctor will tell you what dosage of Zantac is right for you and your specific condition. You should follow your doctor’s instructions exactly when taking Zantac.

If you suspect that you have overdosed with Zantac you should seek emergency help immediately.


Ingredients in Zantac

Zantac has the active ingredient ranitidine hydrochloride in all dosage forms. Oral tablets, both 150 mg and 300 mg also contain the inactive ingredients croscarmellose sodium, D&C Yellow No. 10 Aluminum Lake, hypromellose, magnesium stearate, microcrystalline cellulose, titanium dioxide, and triacetin.

The Zantac 25 mg Efferdose Tablets also contains the inactive ingredients aspartame, monosodium citrate anhydrous, povidone, sodium bicarbonate and sodium benzoate.

Zantac Syrup contains the inactive ingredients alcohol (7.5%), butylparaben, dibasic sodium phosphate, hypromellose, peppermint flavor, monobasic potassium phosphate, propylparaben, purified water, saccharin sodium, sodium chloride, and sorbitol.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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