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Compare Pepcid AC vs. Nexium

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

Key takeaways

Famotidine (Pepcid AC) and esomeprazole (Nexium) are both used to treat conditions caused by too much stomach acid, but they belong to different medication classes. Famotidine is a histamine-2 (H2) antagonist, while esomeprazole is a proton pump inhibitor (PPI). Famotidine works by lowering the amount of stomach acid released by certain cells in your stomach lining, and it starts working within an hour. In contrast, esomeprazole blocks the final step of stomach acid production and can take a few days to show full effects. Famotidine is available both over-the-counter and by prescription, and it can be taken as a tablet or liquid. Esomeprazole is also available over-the-counter and by prescription and comes in capsules, tablets, and a liquid suspension. Famotidine is typically taken twice a day, while esomeprazole is usually taken once a day. Famotidine is generally well-tolerated but can cause headaches and dizziness, whereas esomeprazole can lead to headaches, belly pain, and potential long-term issues like weakened bones. Both medications can interact with other drugs, so it's important to discuss all your medications with a healthcare professional.

Famotidine (Pepcid AC)
Esomeprazole (Nexium)
Famotidine (Pepcid AC)
Esomeprazole (Nexium)
Summary of Pepcid AC vs. Nexium
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 PPI
Esomeprazole (Nexium) is a medication used to treat conditions that are caused by too much stomach acid, such as heartburn or acid reflux. It's available both with a prescription and over the counter (OTC). Take esomeprazole (Nexium) an hour before a meal so that it can start working before you eat. It can take a couple days for you to feel its full effects, so consider taking other quick-acting antacids in the meantime until the medication effect kicks in.
Indications of Pepcid AC vs. Nexium
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
For adults only:

•Heartburn — OTC only

•Lower the risk of stomach ulcer due to nonsteroidal anti-inflammatory drugs (NSAID)

•Lower the risk of duodenal ulcer caused by Helicobacter pylori (H. pylori) infection

•Other medical conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)

For adults and children:

•Gastroesophageal reflux disease (GERD)

•Inflamed esophagus due to GERD
Pros and Cons of Pepcid AC vs. Nexium
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 PPI
Pros

•Can continue to use with antacids, such as calcium carbonate

•Provides longer-lasting relief than some other heartburn medications

•Available as over-the-counter and lower-cost generic options

•Granules or pellets inside the capsules can be mixed with water or applesauce, so convenient for people with difficulty swallowing pills

Cons

•Takes 1 to 4 days for the medication to fully kick in, so not the best choice for immediate heartburn relief

•Significant interaction with clopidogrel (Plavix), which can raise the risk of blood clot

•Long-term use might weaken bones and raise the risk of bone fracture

•Can lower magnesium and vitamin B12 levels
Common Side Effects of Pepcid AC vs. Nexium
Common Side Effects for

•Headache

•Dizziness

•Constipation

•Diarrhea

Common Side Effects for

•Headache (4-8%)

•Belly pain (3-4%)

•Diarrhea (2-4%)

•Nausea (2%)

•Passing gas (more than 1%)

•Constipation (more than 1%)

•Dry mouth (more than 1%)
Warnings of Pepcid AC vs. Nexium
Common Side Effects for

•Agitation, confusion, and other brain-related side effects

•Possible risk of cancer

Common Side Effects for

•Risk of hiding symptoms of a more serious problem

•Sudden kidney problems

•Severe infectious diarrhea

•Bone fractures

•Skin reactions

•Lupus

•Low vitamin B12 and magnesium levels

•Interaction with other medications
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Compare Pepcid AC vs. Nexium

Key takeaways

Summary of Pepcid AC vs. Nexium

Indications of Pepcid AC vs. Nexium

Pros and Cons of Pepcid AC vs. Nexium

Common Side Effects of Pepcid AC vs. Nexium

Warnings of Pepcid AC vs. Nexium

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