Omeprazole OTC (Prilosec)
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- Prilosec OTC (omeprazole 20 mg). Best for: Frequent heartburn 2 or more days a week. See options on Amazon
- Nexium 24HR (esomeprazole 20 mg). Best for: An alternative OTC PPI. See options on Amazon
- Antacid chewables for fast relief. Best for: Occasional, immediate heartburn. See options on Amazon
Prilosec OTC vs Nexium 24HR
| Detail | Prilosec OTC | Nexium 24HR |
|---|---|---|
| Active ingredient | Omeprazole 20 mg (as 20.6 mg omeprazole magnesium) | Esomeprazole 20 mg (as 22.3 mg esomeprazole magnesium trihydrate) |
| Use | Frequent heartburn, 2 or more days a week | Frequent heartburn, 2 or more days a week |
| Course | 1 tablet a day for 14 days; repeat every 4 months if needed | 1 tablet a day for 14 days; repeat every 4 months if needed |
| Ages | 18 and older | 18 and older |
Details are from each product's DailyMed label. Both say swallow the tablet whole; do not crush or chew it.
How the 14-day course works
- Take 1 tablet with a glass of water before eating in the morning.
- Take it every day for 14 days, once every 24 hours.
- Do not take more than 1 tablet a day.
- It may take 1 to 4 days for full effect; the Prilosec OTC label adds that some people get complete relief within 24 hours.
- Do not use for more than 14 days unless directed by your doctor.
- You may repeat a 14-day course every 4 months, but not more often unless a doctor directs.
Because the course is meant to run every day for 14 days, skipping days or taking it only when symptoms flare does not follow the label. If you find you need it more often than one course every 4 months, that is a reason to see your doctor rather than restart on your own.
PPI, H2 blocker or antacid?
NIDDK describes antacids as relieving mild heartburn, H2 blockers as lowering the amount of acid your stomach makes, and PPIs as also lowering stomach acid, adding that PPIs are better at treating GERD symptoms than H2 blockers. Because OTC PPIs need days to reach full effect, they are labeled only for frequent heartburn, not for quick relief.
For occasional heartburn or a trigger meal, see our famotidine guide or antacid chewables guide.
Do not use if
The Prilosec OTC label says do not use it if you are allergic to omeprazole, or if you have trouble or pain swallowing food, vomiting with blood, bloody or black stools, heartburn with lightheadedness, sweating or dizziness, chest pain or shoulder pain with shortness of breath, sweating, pain spreading to the arms, neck or shoulders, or lightheadedness, or frequent chest pain. These may be signs of a serious condition; see your doctor.
Omeprazole may also cause severe skin reactions such as skin reddening, blisters or rash; if an allergic reaction occurs, stop use and seek medical help right away.
Ask a doctor and when to stop
- Ask a doctor before use if you have had heartburn over 3 months, frequent wheezing with heartburn, unexplained weight loss, nausea or vomiting, or stomach pain.
- Ask a doctor or pharmacist if you take a prescription drug, since acid reducers may interact with certain prescription drugs.
- Stop and ask a doctor if heartburn continues or worsens, you need it for more than 14 days or more than 1 course every 4 months, or you get diarrhea, a rash or joint pain.
- Children under 18: ask a doctor; the label notes heartburn in children may sometimes be caused by a serious condition.
Habits that help reflux
NIDDK says a doctor may recommend losing weight if you are overweight, raising your head during sleep, quitting smoking, and changing your eating habits and diet. It advises talking with your doctor if symptoms will not go away with over-the-counter medicines.
Store tablets at 20 to 25 C (68 to 77 F) and protect from moisture, as the label directs. For gas and bloating, see our simethicone gas relief guide.
What to look for when you buy
Prilosec OTC (omeprazole 20 mg)
Best for: Frequent heartburn 2 or more days a week
Its label lists omeprazole 20 mg for a once-daily 14-day course.
Watch out: Not for immediate relief; may take 1 to 4 days for full effect.
See options on AmazonNexium 24HR (esomeprazole 20 mg)
Best for: An alternative OTC PPI
Its label lists esomeprazole 20 mg with the same 14-day course and 4-month repeat rule.
Watch out: Swallow whole; do not crush or chew.
See options on AmazonAntacid chewables for fast relief
Best for: Occasional, immediate heartburn
NIDDK says antacids relieve mild heartburn, while OTC PPIs are not for immediate relief.
Watch out: Avoid daily antacid use without asking your doctor.
See options on AmazonQuestions people ask
- How long does Prilosec OTC take to work?
- The label says it may take 1 to 4 days for full effect; some people get relief within 24 hours.
- Can I take omeprazole for more than 14 days?
- Not unless a doctor directs; you may repeat a 14-day course every 4 months.
- When should I take omeprazole?
- Once a day, before eating in the morning, with a glass of water.
- Is omeprazole better than famotidine?
- NIDDK says PPIs are better at treating GERD symptoms; famotidine works for occasional heartburn.
- Is Nexium the same as Prilosec?
- No. Nexium 24HR is esomeprazole and Prilosec OTC is omeprazole; both are 20 mg PPIs with the same 14-day course.
- Can I take omeprazole for occasional heartburn?
- The labels say it treats frequent heartburn and is not intended for immediate relief, so an antacid or famotidine fits occasional heartburn better.
Sources
- Prilosec OTC (omeprazole magnesium) label (dailymed.nlm.nih.gov), DailyMed, U.S. National Library of Medicine
- Nexium 24HR (esomeprazole magnesium) tablet label (dailymed.nlm.nih.gov), DailyMed, U.S. National Library of Medicine
- Treatment for GER and GERD (niddk.nih.gov), National Institute of Diabetes and Digestive and Kidney Diseases