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Famotidine vs. Omeprazole

Famotidine (Pepcid) is a type of acid reducer called a histamine-2 (H2) antagonist. It helps treat problems caused by too much stomach acid. Over-the-counter famotidine (Pepcid or Pepcid AC) can help with heartburn in people who are 12 and up. Prescription-only famotidine is for people with more ongoing stomach acid problems and stomach or gut ulcers. This medication is taken by mouth once or twice a day. It usually starts to work within an hour and lasts several hours. Side effects include headache, dizziness, and constipation.

• Over-the-counter famotidine:

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

• Prescription famotidine:

  • Stomach ulcers
  • Intestinal ulcers
  • Heartburn (GERD)
  • Erosive esophagitis (inflammation of the esophagus) due to GERD
  • Other conditions that cause too much stomach acid (e.g., Zollinger-Ellison syndrome)

• Headache
• Dizziness
• Constipation
• Diarrhea

• Confusion and other side effects related to the nervous system in some people
• Masking of possible stomach cancer

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.

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

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%)

• 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