Generic Name: Ranitidine

  • What is Zantac?

    Zantac is used to treat ulcers in the intestines and stomach. It is also used to prevent the occurrence of ulcers, to treat and prevent the erosion in the esophagus (the tube that connects your mouth and stomach) caused by acid, to reduce stomach acid in certain diseases where the stomach secretes too much acid, and to treat gastroesophageal reflux disease (GERD).

    Zantac belongs to a class of drugs called H2 receptor antagonists, which decrease the amount of acid secreted into your stomach.

  • What is the most important information I should know about Zantac?

    Even if Zantac relieves your stomach or ulcer-related symptoms, it is still important to finish Zantac therapy for the prescribed amount of time.

    Use caution when taking Zantac if you have kidney or liver problems. If you have porphyria (a disorder that interferes with how your body produces heme, which is the oxygen-carrying component of your red blood cells), do not take Zantac because it may increase your risk of experiencing an acute porphyric attack.

    Successful response to Zantac therapy does not rule out the possible presence of stomach cancer.

  • Who should not take Zantac?

    You should not take Zantac if you are allergic or sensitive to it or any of its ingredients.

  • What should I tell my doctor before I take the first dose of Zantac?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Zantac. Also, talk to your doctor about your complete medical history, especially if you have a history of stomach or intestinal ulcers, or any type of kidney or liver problems.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Active Duodenal Ulcer (ulcer in the upper intestine), Stomach Ulcer, GERD, or Maintenance of Healing of Erosive Esophagitis (inflammation and ulceration of the esophagus)

    Adults: The usual dose is 150 milligrams (mg) or 2 teaspoons of Zantac syrup taken twice a day. For those with an active duodenal ulcer, an alternative dose of 300 mg or 4 tsp of Zantac syrup can be taken once daily in the evening or at bedtime.

    Duodenal and Stomach Ulcers

    Children ages 1 month to 16 years: Your doctor will prescribe the appropriate dose for your child based on their body weight.

    GERD and Erosive Esophagitis

    Children ages 1 month to 16 years: Your doctor will prescribe the appropriate dose for your child based on their body weight.

    Maintenance of Healing of Duodenal and Gastric Ulcers

    Adults: The usual dose is 150 mg or 2 tsp of Zantac syrup taken once daily at bedtime.

    Children ages 1 month to 16 years: Your doctor will prescribe the appropriate dose for your child based on their body weight.

    Erosive Esophagitis

    Adults: The usual dose is 150 mg or 2 tsp of Zantac syrup taken four times a day.

    Hypersecretory Conditions (such as Zollinger-Ellison Syndrome)

    Adults: The usual dose is 150 mg or 2 tsp of Zantac syrup taken twice daily. Your doctor may increase your dose depending on your condition.

  • How should I take Zantac?

    Zantac can be taken with or without food and should be taken at the same time every day.

    Antacids may be used if additional pain relief is needed.

    Zantac 25 EFFERdose tablets should be prepared by dissolving 1 tablet in a teaspoonful of water. Once the tablet is completely dissolved, administer the solution to the infant/child. You may use a medicine dropper or oral syringe if desired.

  • What should I avoid while taking Zantac?

    Avoid drinking excessive amounts of caffeine or alcohol while taking Zantac. You should also avoid any spicy foods or other products that may irritate your stomach and intestines.

  • What are possible food and drug interactions associated with Zantac?

    If Zantac is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Zantac with the following: atazanavir, delavirdine, gefitinib, glipizide, ketoconazole, midazolam, procainamide, triazolam, or warfarin.

  • What are the possible side effects of Zantac?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: constipation, nausea, vomiting, abdominal pain, headache, irregular heartbeat, pneumonia, dizziness, liver problems, rash, blood cell changes, possible allergic reaction including anaphylaxis (trouble breathing, swelling of airway)

  • Can I receive Zantac if I am pregnant or breastfeeding?

    The effects of Zantac during pregnancy are unknown. Zantac is excreted in breast milk. Tell your doctor immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of Zantac?

    If you forget to take Zantac, take it as soon as you remember. If it is closer to your next scheduled dose, skip the dose you missed and take Zantac according to your regular dosing schedule. Do not take two doses at once.

  • How should I store Zantac?

    Store at room temperature.

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