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Compare Tagamet HB vs. Prilosec OTC

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

Key takeaways

Cimetidine (Tagamet HB) and omeprazole (Prilosec) are both used to treat heartburn and other stomach acid problems, but they belong to different classes of medications. Cimetidine is a histamine H2 receptor antagonist (H2RA) that works by blocking acid production in the stomach, while omeprazole is a proton pump inhibitor (PPI) that blocks the final step of acid production. Cimetidine can be taken multiple times a day and is available in both over-the-counter (OTC) and prescription forms, whereas omeprazole is typically taken once daily, 30 minutes before breakfast. Omeprazole is also available OTC and by prescription. Cimetidine may start working faster but might not be as effective with long-term use, and it has more drug interactions compared to omeprazole. Omeprazole, on the other hand, provides longer-lasting relief but takes 1 to 4 days to fully work and is not recommended for long-term use due to potential serious side effects like bone fractures and kidney problems. Both medications can cause headaches and stomach issues, but omeprazole has a broader range of potential side effects, including severe diarrhea and low vitamin B12 levels.

Cimetidine (Tagamet HB)
Omeprazole (Prilosec)
Cimetidine (Tagamet HB)
Omeprazole (Prilosec)
Summary of Tagamet HB vs. Prilosec OTC
Summary for Histamine H2 receptor antagonist (H2RA)
Cimetidine (Tagamet HB) is a histamine H2 receptor antagonist (H2RA) that lowers how much acid is made in the stomach. The over-the-counter (OTC) version relieves and prevents heartburn in people 12 years and older. Higher strengths of cimetidine are prescription only and are used to treat acid reflux, stomach and gut ulcers, and other stomach acid problems in people 16 years and older. Cimetidine (Tagamet HB) is taken by mouth one to four times a day, depending on what stomach problem you have. This medication has few side effects, which can include headache, dizziness, and diarrhea.
Summary for PPI
Omeprazole (Prilosec) is a proton pump inhibitor (PPI). Over-the-counter (OTC) omeprazole (Prilosec) can ease heartburn, while the prescription version can treat gastroesophageal reflux disease (GERD) and other conditions involving too much stomach acid. Omeprazole (Prilosec) is taken by mouth, typically once daily 30 minutes before breakfast. Some of the more common side effects of omeprazole (Prilosec) include headache, stomach pain, and nausea. It's available as both brand name and generic medications.
Indications of Tagamet HB vs. Prilosec OTC
Indications for

•Heartburn related to indigestion and sour stomach - OTC only

•Erosive gastroesophageal reflux disease (GERD) - prescription only

•Gastric and duodenal ulcers - prescription only

•Conditions that cause too much stomach acid (such as Zollinger-Ellison syndrome) - prescription only

Indications for
For adults only:

•Heartburn — OTC only

•Stomach or duodenal ulcer

•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 Tagamet HB vs. Prilosec OTC
Pros and Const for Histamine H2 receptor antagonist (H2RA)
Pros

•Available as an OTC product for heartburn only

•Available as a tablets and an oral solution

Cons

•Interacts with many medications, including warfarin (Coumadin) and propranolol

•Might not work as well as you continue taking the medication (when taken long-term)

Pros and Const for PPI
Pros

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

•Provides longer-lasting relief than some other heartburn medications

•Can use for adults, as well as children with certain medical conditions

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

Cons

•Interacts with many medications, such as digoxin (Lanoxin) and clopidogrel (Plavix)

•Won't provide immediate heartburn relief

•Usually taken 30 to 60 minutes before eating a meal for best results

•Not recommended for long-term treatment, except for certain conditions, because of risk of serious side effects
Common Side Effects of Tagamet HB vs. Prilosec OTC
Common Side Effects for

•Diarrhea

•Headache

•Dizziness

•Sleepiness

Common Side Effects for
Adults

•Headache (7%)

•Belly pain (5%)

•Nausea (4%)

•Diarrhea (4%)

•Vomiting (3%)

•Passing gas (3%)

Children — similar to the above, with the addition of:

•Respiratory system problems (up to 75%)

•Fever (up to 33%)

•Ear infection (up to 22%)
Warnings of Tagamet HB vs. Prilosec OTC
Common Side Effects for

•Speak with provider if symptoms don't go away or come back

•Confusion

•Drug interactions

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

•Inaccurate lab work
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Compare Tagamet HB vs. Prilosec OTC

Key takeaways

Summary of Tagamet HB vs. Prilosec OTC

Indications of Tagamet HB vs. Prilosec OTC

Pros and Cons of Tagamet HB vs. Prilosec OTC

Common Side Effects of Tagamet HB vs. Prilosec OTC

Warnings of Tagamet HB vs. Prilosec OTC

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