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Compare Pepcid AC vs. Bismuth subsalicylate

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Famotidine (Pepcid AC) and bismuth subsalicylate (Pepto-Bismol) are both used to treat stomach-related issues, but they work differently and are used for different conditions. Famotidine is a histamine-2 (H2) antagonist that reduces stomach acid and is used for heartburn, stomach ulcers, and conditions like GERD. It is available both over-the-counter and by prescription. On the other hand, bismuth subsalicylate is an antidiarrheal that treats diarrhea and symptoms of an upset stomach, such as nausea and gas. It is only available over-the-counter. Famotidine is typically taken twice a day, while bismuth subsalicylate can be taken every 30 minutes to an hour as needed. Famotidine can cause headaches and dizziness, whereas bismuth subsalicylate can cause dark-colored stools and a dark tongue. Additionally, bismuth subsalicylate should not be used by children under 12, while famotidine can be used in younger children under medical guidance.

  • Famotidine (Pepcid AC)
    Bismuth subsalicylate (Pepto-Bismol)
  • Famotidine (Pepcid AC)
    Bismuth subsalicylate (Pepto-Bismol)

  • Summary of Pepcid AC vs. Bismuth subsalicylate

    Summary for Histamine H2 antagonist

    Famotidine (Pepcid AC) is a histamine-2 (H2) antagonist that's used to treat conditions that cause too much stomach acid to build up, such as heartburn and stomach or intestinal ulcers (sores). It starts to work within an hour and lasts for several hours. It's available as a tablet and a liquid, and is taken by mouth twice per day. Side effects of famotidine (Pepcid AC) include headache, dizziness, and constipation.

    Summary for Antidiarrheal

    Bismuth subsalicylate (Pepto-Bismol) is a salicylate antidiarrheal medication. It's used to ease diarrhea and symptoms of an upset stomach (e.g., gas, nausea) in adults and kids ages 12 years and older. This medication is taken by mouth, typically once every 30 minutes to an hour, as needed. Bismuth subsalicylate (Pepto-Bismol) is found over the counter in several different formulations, such as chewable tablets and oral solutions. Side effects of this medication include nausea, changes in taste, dark-colored tongue, and black stool.

  • Indications of Pepcid AC vs. Bismuth subsalicylate

    Indications for

    Over-the-counter (OTC) famotidine

    •Prevention and treatment of heartburn (gastroesophageal reflux disease or GERD)

    Prescription famotidine

    •Gastric ulcer (open sore in the stomach)
    •Duodenal ulcer (open sore in the first part of the small intestine)
    •Heartburn (GERD)
    •Erosive esophagitis due to GERD (inflammation of the esophagus)
    •Other conditions that cause too much stomach acid secretion (i.e., Zollinger-Ellison syndrome)
    Indications for
    •Diarrhea
    •Travelers' diarrhea
    •Symptoms of upset stomach (e.g., heartburn, indigestion, nausea, gas, belching (burping), fullness)

  • Pros and Cons of Pepcid AC vs. Bismuth subsalicylate

    Pros and Const for Histamine H2 antagonist
    Pros
    •Starts to work within an hour and lasts for up several hours
    •Available as both a generic and over-the-counter option
    •If needed, can be used with some other acid-lowering medications, such as antacids (e.g., calcium carbonate (Tums)) or PPIs
    •Generally well-tolerated with little side effects
    •Available as a oral suspension, a good option for people who can't swallow tablets
    Cons
    •Antacids start to work more quickly than famotidine (Pepcid AC)
    •PPIs work better at healing and preventing stomach ulcers than famotidine (Pepcid AC).
    •Needs to be taken twice daily for most conditions
    •Not the best option for people with kidney problems
    Pros and Const for Antidiarrheal
    Pros
    •Treats a wide variety of stomach-related symptoms
    •Available as a lower-cost generic medication
    •Available in chewable tablets or liquid for people who have difficulty swallowing pills
    •Can be taken with or without food
    Cons
    •Shouldn’t be taken for longer than 2 days
    •Can cause darkening of the tongue or stools
    •Might need to take it multiple times per day
    •Not for children less than 12 years of age due to higher risk of Reye's syndrome

  • Common Side Effects of Pepcid AC vs. Bismuth subsalicylate

    Common Side Effects for
    •Headache
    •Dizziness
    •Constipation
    •Diarrhea
    Common Side Effects for
    •Nausea
    •Bitter taste in mouth
    •Diarrhea
    •Dark-colored stools

  • Warnings of Pepcid AC vs. Bismuth subsalicylate

    Common Side Effects for
    •Agitation, confusion, and other brain-related side effects
    •Possible risk of cancer
    Common Side Effects for
    •Reye's syndrome in children
    •Salicylate toxicity
    •Allergic reactions

  • Prices with our coupons for Pepcid AC vs. Bismuth subsalicylate

    Learn more about Famotidine
    Learn more about Bismuth subsalicylate

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