Tagamet vs. Zantac

Are Tagamet and Zantac the Same Thing?

Tagamet (cimetidine) and Zantac (ranitidine hydrochloride) are histamine receptor antagonists used to treat and prevent ulcers.

Tagamet is also used to treat conditions that cause the stomach to produce too much acid, and to treat gastroesophageal reflux disease (GERD).

What Are Possible Side Effects of Tagamet?

Common side effects of Tagamet include:

  • headache,
  • dizziness,
  • drowsiness,
  • depression,
  • agitation,
  • breast swelling or tenderness (in men),
  • joint or muscle pain,
  • skin rash,
  • diarrhea,
  • nausea, or
  • constipation.

Tell your doctor if you experience unlikely but serious side effects of Tagamet including:

  • mental/mood changes (e.g., confusion, hallucinations),
  • trouble urinating, or
  • decreased sexual ability (with very high doses).

What Are Possible Side Effects of Zantac?

Common side effects of Zantac include:

  • constipation,
  • diarrhea,
  • fatigue,
  • headache (may be severe),
  • drowsiness,
  • dizziness,
  • sleep problems (insomnia),
  • decreased sex drive,
  • impotence,
  • difficulty having an orgasm,
  • muscle pain,
  • stomach pain,
  • nausea,
  • vomiting,
  • diarrhea,
  • constipation,
  • or swollen or tender breasts (in men).

What Is Tagamet?

Tagamet (cimetidine) is a histamine receptor antagonist used to treat and prevent certain types of ulcer, and to treat conditions that cause the stomach to produce too much acid. Tagamet is also used to treat gastroesophageal reflux disease (GERD), when stomach acid backs up into the esophagus and causes heartburn.

What Is Zantac?

Zantac (ranitidine hydrochloride) is a H2 (histamine-2) receptor blocker used for treating and preventing ulcers in the duodenum and stomach. Zantac is also used for treating:

  • heartburn,
  • erosive esophagitis,
  • and Zollinger Ellison syndrome.

What Drugs Interact With Tagamet?

Tagamet may interact with blood thinners, clopidogrel, phenytoin, nifedipine, metronidazole, propranolol, chlordiazepoxide, lidocaine, diazepam, theophylline, depression or anxiety medications. Tell your doctor all medications you use.

What Drugs Interact With Zantac?

Zantac may interact with ketoconazole, atazanavir, and blood thinners such as warfarin.

Zantac may also interact with triazolam, procainamide, riazolam, midazolam, glipizide, delavirdine, and gefitinib.

How Should Tagamet Be Taken?

Dose of Tagamet depends on the condition being treated and the patient's response to the medication.

How Should Zantac Be Taken?

Zantac is available in tablet, syrup, and injectable formulations.

  • adults and children 12 years and over:
    • to relieve symptoms, swallow 1 tablet with a glass of water
    • to prevent symptoms, swallow 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 (do not take more than 2 tablets in 24 hours)
  • children under 12 years: ask a doctor

Other Information

  • do not use if printed foil under bottle cap is open or torn (bottles)
  • do not use if individual blister unit is open or torn (blisters)
  • do not use if individual foil packet is open or torn (pouch)
  • store at 20°-25°C (68°-77°F)
  • avoid excessive heat or humidity
  • this product is sodium and sugar free

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Prestige Consumer Healthcare, Inc. Tagamet Product Information.


Sanofi. Zantac Consumer Product Information.

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