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What is Omeprazole and How Does It Work?

Omeprazole is an active ingredient in medications used to treat frequent heartburn. Frequent heartburn is caused by stomach acid refluxing into the esophagus and happens 2 or more times a week.

Omeprazole is a Proton Pump Inhibitor (PPI), which is a class of drugs used to treat frequent heartburn symptoms by reducing the acid in the stomach that can cause heartburn. Omeprazole works by binding to the acid-producing pumps in the stomach and turning them off, blocking the acid at the source. It starts working as early as an hour after taking the first dose but may take 1-4 days for full effect.

Over-the-counter Omeprazole

To find omeprazole over-the-counter, look for Prilosec OTC! Omeprazole is the active ingredient in Prilosec OTC , treating your frequent heartburn with 1 pill a day.* Prilosec OTC has a unique delayed-release formula that passes through the tough stomach acid, to block the acid at the source… so you don’t get heartburn in the first place.* The Prilosec OTC dose is one omeprazole 20mg delayed-release tablet (equivalent to 20.6mg omeprazole magnesium) each day. This one tablet enables 24-hours of zero heartburn and the recommended treatment is only 14-days!*

Omeprazole Benefits

The active ingredient omeprazole works to fight heartburn differently from treatments like acid controllers/H2s or antacids. One of the best benefits of omeprazole is experiencing heartburn relief for 24 hours after only taking 1 pill a day.* But it’s not the only benefit. Omeprazole is a proton pump inhibitor (PPI) and PPIs are the strongest class of frequent heartburn medicines. They work to block the acid at the source…something that antacids just can’t do.


  • Provide immediate relief by neutralizing acid in the esophagus

  • Do not reduce acid production at its source, and can actually turn on acid production, which may lead to more heartburn

  • Heartburn relief lasts 1-3 hours and you may need to take several times throughout the day

Acid controllers:

  • Partially reduce acid production by blocking only one of the signals that tell your body to produce acid

  • Heartburn relief lasts 12 hours, so by the time you sit down for dinner, you might need to take a second dose

Prilosec OTC’s Omeprazole:

  • Blocks many of the stomach pumps that produce acid

  • Reduces the stomach acid that causes heartburn

  • Heartburn relief lasts for 24 hours with 1 pill a day*

  • Has a unique delayed release formula

Imagine taking one Prilosec OTC pill every day for 14 days (no more than 3 times a year) and experiencing zero heartburn.* So when you wake up, you don’t have heartburn and when you go to sleep that same day, you still don’t have heartburn! It may take 1-4 days for full effect (but some receive complete relief with 24 hours). Prilosec OTC omeprazole could be the answer to your many uncomfortable nights.

Talk to your healthcare provider about the heartburn symptoms you’re experiencing. Fun fact: Prilosec OTC has been the #1 Doctor Recommended frequent heartburn medicine for 14 straight years.† So ask them about Prilosec OTC and omeprazole - it could be the right treatment for you.