It’s available via prescription and over-the-counter (OTC).
It can take a few days of taking it before symptoms start to subside.
Additionally, how long it takes to work may depend on the condition being treated.

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This is true of all forms of omeprazole (capsule, tablet, and liquid suspension).
How long depends on the specific condition being treated.
For example, when healthcare providers prescribe omeprazole forerosive esophagitis, omeprazole helps reduce acid production rapidly.
This often results in significant or complete relief within 14 days.
If you stop taking omeprazole, normal stomach acid production restarts within three to five days.
Be sure to take it according to your providers instructions.
Acid reflux is typically mild and occasional, causing temporary heartburn.
However, acid reflux often results in longer-lasting, more painfulsymptoms of GERD.
Certain foods or drinks maytrigger acid reflux.
Eliminating these from your diet often reduces symptoms.
Experts also recommend elevating your head during sleep.
This allows gravity to help prevent acid from entering your esophagus.
In some cases, healthcare providers may recommend an acid-reducing medication for GERD.
It belongs to the PPI drug class.
This is commonly known as off-label use.
Omeprazole is commonly used off-label for long-term prevention of stomach ulcers in individuals at high risk for developing them.
Additionally, omeprazole is an active ingredient in a combination drug called Talicia (amoxicillin/omeprazole/rifabutin).
Talicia is an oral capsule that works to eliminate harmful bacteria in the stomach known asH.
How Does Omeprazole Work?
Omeprazole reduces stomach acid through the same mechanism as other proton pump inhibitors.
It works by blocking receptors in the stomach lining responsible for releasing protons, which increase acidity.
When omeprazole binds to these pumps, it stops the release of protons, decreasing acidity.
This means this medication isnt helpful if taken occasionally or as needed.
Instead, omeprazole takes time to start working, which can vary depending on the reason youre taking it.
For heartburn, this drug may take one to four days before you notice some improvement in your symptoms.
In some cases, it may take up to four weeks to control stomach acid production fully.
Dosing Guidelines
The recommended dose of omeprazole varies depending on your age and the condition being treated.
The table below summarizes some of the recommended dosage guidelines for adults taking omeprazole.
This is not meant to be a complete dosage guide.
In children younger than 16 years, dosing depends on weight and product.
Omeprazole delayed-release capsules are approved for those 2 years and older.
A liquid suspension is approved for infants 1 month and older, depending on the reason for use.
Safe Consumption Guidelines
Omeprazole is typically taken once daily before a meal.
Take it around the same time each day.
If a missed dose occurs, kindly take it as soon as possible.
But if its almost time for your next dose, skip the missed dose.
Interactions
Certain medications may interact with omeprazole, resulting in negative side effects or reduced effectiveness.
Only take OTC omeprazole for 14 days as instructed on the medication label.
In some cases, longer treatment is required, but only under the direction of a healthcare provider.
When used as directed for short periods of time, omeprazole doesnt usually cause side effects.
However, when omeprazole is taken for a year or longer, additional serious side effects may occur.
Alternative Treatment Options
Lifestyle changescan be a practical approach to treating and preventing GERD.
However, omeprazole does not provide instant relief.
It may take one to four days of treatment before you notice an improvement in your symptoms.
Complete relief may take two to four weeks or longer, depending on the specific condition being treated.
Be sure to keep the product away from moisture.
Both the prescription and over-the-counter versions of Prilosec contain the same active ingredient: omeprazole.
The OTC form is only available in a 20 mg strength, while Rx omeprazole comes in multiple strengths.
For severe acid reflux or symptoms that keep coming back, see a healthcare provider for advice.
Food and Drug Administration.Orange book: approved drug products with therapeutic equivalence evaluations.
DailyMed.Omeprazole delayed-release tablet label.
National Institute of Diabetes and Digestive and Kidney Diseases.Acid reflux (GER & GERD) in adults.
Food and Drug Administration.Prilosec (omeprazole magnesium) for delayed-release suspension label.