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Compare Pepcid AC vs. Prevacid

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

Key takeaways

Famotidine (Pepcid AC) and lansoprazole (Prevacid) are both used to treat conditions related to excess stomach acid, but they belong to different medication classes. Famotidine is a histamine-2 (H2) antagonist, which works by lowering the amount of acid released in the stomach. It starts working within an hour and is available both over-the-counter and by prescription. On the other hand, lansoprazole is a proton pump inhibitor (PPI) that blocks acid from being pumped into the stomach, taking about three days to fully kick in. Famotidine is typically taken twice a day, while lansoprazole is usually taken once daily. Famotidine can cause side effects like headache, dizziness, and constipation, whereas lansoprazole might lead to diarrhea and belly pain, with long-term use potentially causing bone fractures and low magnesium levels. Lansoprazole is also available in a form that can be sprinkled on food, which can be helpful if you have trouble swallowing pills.

Famotidine (Pepcid AC)
Lansoprazole (Prevacid)
Famotidine (Pepcid AC)
Lansoprazole (Prevacid)
Summary of Pepcid AC vs. Prevacid
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
Lansoprazole (Prevacid) a proton-pump inhibitor (PPI). It treats heartburn, gastroesophageal reflux disease (GERD), and other similar conditions by lowering the amount of acid produced in the stomach. Lansoprazole (Prevacid) is available over the counter (OTC) for adults only, while providers can prescribe lansoprazole (Prevacid) for children and adults. Lansoprazole (Prevacid) is taken by mouth, typically once daily for most conditions. Although there aren't many noticeable side effects on a day-to-day basis, long-term use of lansoprazole (Prevacid) can raise certain risks like bone fractures.
Indications of Pepcid AC vs. Prevacid
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:

•Frequent heartburn (2 or more days a week) - OTC only

•Stomach or duodenal ulcer

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

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

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

For adults and children:

•Gastroesophageal reflux disease (GERD)

•Erosive esophagitis (EE)
Pros and Cons of Pepcid AC vs. Prevacid
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

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

•Capsules can be opened and sprinkled over soft foods (e.g., applesauce, yogurt)

•Typically few to no noticeable day-to-day side effects

Cons

•Takes about 3 days for the medication to fully kick in, so not the best choice for immediate heartburn relief

•Might cause or worsen lupus

•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. Prevacid
Common Side Effects for

•Headache

•Dizziness

•Constipation

•Diarrhea

Common Side Effects for

•Diarrhea (4%)

•Belly pain (2%)
Warnings of Pepcid AC vs. Prevacid
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

•Caution use in people with phenylketonuria (PKU) - orally disintegrating tablets only
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Compare Pepcid AC vs. Prevacid

Key takeaways

Summary of Pepcid AC vs. Prevacid

Indications of Pepcid AC vs. Prevacid

Pros and Cons of Pepcid AC vs. Prevacid

Common Side Effects of Pepcid AC vs. Prevacid

Warnings of Pepcid AC vs. Prevacid

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