Tagamet vs. Pepcid

Are Tagamet and Pepcid the Same Thing?

Tagamet (cimetidine) and Pepcid (famotidine) are histamine receptor antagonists used to treat and prevent certain types of ulcer, to treat conditions that cause the stomach to produce too much acid, and to treat gastroesophageal reflux disease (GERD).

Pepcid is also used to treat Zollinger-Ellison syndrome.

Both Tagamet and Pepcid are available over-the-counter (OTC) and as generics.

Side effects of Tagamet and Pepcid that are similar include headache, dizziness, joint or muscle pain, diarrhea, nausea, or constipation.

Side effects of Tagamet that are different from Pepcid include drowsiness, depression, agitation, breast swelling or tenderness (in men), or skin rash.

Side effects of Pepcid that are different from Tagamet include fatigue, weakness, mood changes, insomnia, dry mouth, or vomiting.

Both Tagamet and Pepcid may interact with antacids or ketoconazole.

Tagamet may also interact with antidepressants or blood thinners.

Pepcid may also interact with alcohol, atazanavir, itraconazole, cefditoren, dasatinib, delavirdine, fosamprenavir, or aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs).

What Are Possible Side Effects of Tagamet?

Common side effects of Tagamet include:

  • drowsiness,
  • dizziness,
  • weakness,
  • blurred vision,
  • dry eyes,
  • dry mouth,
  • vomiting,
  • constipation,
  • abdominal bloating,
  • stuffy nose,
  • sinus pain, or
  • flushing (warmth, redness, or tingly feeling).

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

  • decreased sweating,
  • fast/irregular heartbeat,
  • mental/mood changes (such as confusion, hallucinations, agitation, nervousness, unusual excitement),
  • difficulty urinating, or
  • decreased sexual ability.

What Are Possible Side Effects of Pepcid?

Common side effects of Pepcid include:

  • constipation,
  • diarrhea,
  • fatigue,
  • dizziness,
  • weakness,
  • mood changes,
  • headache,
  • insomnia,
  • muscle pain or cramps,
  • joint pain,
  • dry mouth,
  • nausea, or
  • vomiting.

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 Pepcid?

Pepcid (famotidine) is an H2-blocker used to treat and prevent recurrence of stomach and duodenal ulcers. Pepcid is also useful in managing heartburn, gastroesophageal reflux disease and Zollinger-Ellison syndrome. Pepcid is available as a generic drug.

What Drugs Interact With Tagamet?

Tagamet may interact with amantadine, quinidine, antihistamines, decongestants, appetite suppressants, phenothiazines, or antidepressants. Tell your doctor all prescription and over-the-counter medications you use. During pregnancy, Tagamet should be used only when prescribed. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

What Drugs Interact With Pepcid?

Pepcid may interact with atazanavir, itraconazole, ketoconazole, or aspirin or other NSAIDs (nonsteroidal anti-inflammatory drugs). Tell your doctor all medications and supplements you use.

How Should Tagamet Be Taken?

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

How Should Pepcid Be Taken?

Pepcid (famotidine) dosage depends on the condition being treated.


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Prestige Consumer Healthcare. Tagamet Product Information.


McNeil Consumer Pharmaceuticals Co. Pepcid Product Information.


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