Nexium vs. Prilosec: Differences, similarities, and which is better for you

Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

Are you experiencing heartburn? If so, you’re not alone—more than 60 million Americans experience heartburn at least once a month, and many of these patients have heartburn symptoms every day.

Nexium (esomeprazole magnesium) and Prilosec (omeprazole magnesium) are two medications in a drug class called proton pump inhibitors, or PPIs. PPIs work by blocking and decreasing acid production, thereby preventing heartburn and achieving acid control.

These drugs are approved by the FDA. They are used to treat symptoms of gastroesophageal reflux disease and other gastrointestinal conditions. Although both Nexium and Prilosec are PPIs, they do have some differences, which we discuss below.

What are the main differences between Nexium and Prilosec?

Nexium (What is Nexium?) is known by its generic name of esomeprazole, and Prilosec (What is Prilosec?) is known by its generic name of omeprazole. The generic names sound similar for a reason—esomeprazole is a chemical isomer of omeprazole. Both drugs are made up of the same chemicals but are arranged in different ways.

Both Nexium and Prilosec are available in brand and generic, and as prescription drugs and over-the-counter as Nexium OTC and Prilosec OTC. The dosage and length of treatment vary by age and the condition being treated.

Main differences between Nexium and Prilosec
	Nexium	Prilosec
Drug class	Proton pump inhibitor (PPI)	Proton pump inhibitor (PPI)
Brand/generic status	Brand and generic	Brand and generic
What is the generic name?	Esomeprazole magnesium	Omeprazole magnesium
What form(s) does the drug come in?	Rx: delayed-release capsules, suspension, packets, injection OTC: capsules, mini capsules, tablets	Rx: delayed-release capsules, suspension OTC: delayed-release tablets
What is the standard dosage?	Varies by indication: usually 20-40 mg once or twice daily (adult dose)	Varies by indication: usually 20-40 mg once or twice daily (adult dose)
How long is the typical treatment?	10 days to 6 months, many patients take for longer	10 days to 8 weeks, many patients take for longer
Who typically uses the medication?	Adults and children	Adults and children

Conditions treated by Nexium vs. Prilosec

Nexium and Prilosec are both used in the treatment of gastroesophageal reflux disease (GERD), to eradicate H. pylori to lower the risk of duodenal ulcer recurrence, and for pathological hypersecretory conditions.

Nexium is also indicated for the risk reduction of NSAID-associated gastric ulcer.

Prilosec is also indicated for the treatment of active duodenal ulcer or active benign gastric ulcer, treatment of erosive esophagitis (EE) due to acid-mediated GERD, and maintenance of healing of EE due to acid-mediated GERD.

Condition	Nexium	Prilosec
Treatment of gastroesophageal reflux disease (GERD)	Yes	Yes
Risk reduction of NSAID-associated gastric ulcer	Yes	Off-label
H. pylori eradication to reduce the risk of duodenal ulcer recurrence	Yes	Yes
Pathological hypersecretory conditions (including Zollinger-Ellison Syndrome)	Yes	Yes
Treatment of active duodenal ulcer	Off-label	Yes
Treatment of active benign gastric ulcer	Off-label	Yes
Treatment of erosive esophagitis (EE) due to acid-mediated GERD	Off-label	Yes
Maintenance of healing of EE due to acid-mediated GERD	Off-label	Yes

Is Nexium or Prilosec more effective?

In trials comparing standard doses of Nexium 40 mg and Prilosec 20 mg (along with other PPIs) in patients with GERD symptoms, Nexium provided the most acid control out of all of the drugs. In another study, patients treated with Nexium experienced faster symptom relief than patients treated with Prilosec and other PPIs. Although Nexium may be more effective, both drugs are quite popular among prescribers.

The best medication is the one that works best for you, with the least amount of side effects. Consult your healthcare provider, who can help select the best drug for you based on your symptoms, medical condition(s), and other drugs you take that could interact with Nexium or Prilosec.

Coverage and cost comparison of Nexium vs. Prilosec

Both Nexium and Prilosec are usually covered by insurance and Medicare Part D. Usually, the prescription generic version is covered. The OTC versions are usually only covered (with a prescription) under certain insurance. Copays vary by plan.

The out-of-pocket price for 30 capsules of generic Nexium 40 mg can be over $300. You can pay under $50 by using a SingleCare card at participating pharmacies

The out-of-pocket price for 30 capsules of generic Prilosec 20 mg averages $50 or more. With a SingleCare omeprazole coupon the price starts at $15 depending on which pharmacy you use.

	Nexium	Prilosec
Typically covered by insurance?	Yes, as Rx generic (usually not OTC)	Yes, as Rx generic (usually not OTC)
Typically covered by Medicare Part D?	Yes, as Rx generic (usually not OTC)	Yes, as Rx generic (usually not OTC)
Standard dosage	Example: 40 mg capsule daily	Example: 20 mg capsule daily
Typical Medicare Part D copay	$14	$0-$20
SingleCare cost	$46	$9-$20

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Common side effects of Nexium vs. Prilosec

The most common side effects of Nexium are abdominal pain, diarrhea, headache, and nausea. The most common side effects of Prilosec are headache, abdominal pain, diarrhea, and nausea. Both medications are generally well-tolerated.

This is not a full list of side effects. Consult your healthcare provider for a full list of adverse effects.

	Nexium		Prilosec
Side Effect	Applicable?	Frequency	Applicable?	Frequency
Abdominal pain	Yes	3.8-5%	Yes	5%
Constipation	Yes	2%*	Yes	2%
Diarrhea	Yes	4.3%	Yes	4%
Nausea	Yes	4%*	Yes	4%
Headache	Yes	3.8%	Yes	7%
Vomiting	Yes	<1%	Yes	3%
Flatulence	Yes	3%*	Yes	3%
Rash	Yes	<1%	Yes	2%

*Percent not reported but occurred at similar rate to Prilosec
Source: DailyMed (Nexium), DailyMed (Prilosec)

Drug interactions of Nexium and Prilosec

Because Nexium and Prilosec are similar drugs with similar structures, they have similar drug interactions. PPIs should not be taken with antiretrovirals. Nexium or Prilosec could decrease levels of atazanavir or nelfinavir, so the antiretroviral would not properly, and the interaction could even cause drug resistance. On the other hand, taking saquinavir with a PPI has the opposite effect, increasing levels of saquinavir, which could lead to toxicity.

Combining Nexium or Prilosec with digoxin can increase levels of digoxin and lead to toxicity. Taking Nexium or Prilosec with warfarin can lead to increased levels of warfarin, which could cause bleeding or even death. Nexium or Prilosec can interact with Plavix (clopidogrel), diazepam, cilostazol, and other drugs. This is not a complete list of drug interactions. Consult your healthcare provider for a full list of drug interactions.

Drug	Drug Class	Nexium	Prilosec
Atazanavir Nelfinavir Saquinavir	Antiretrovirals	Yes	Yes
Digoxin	Cardiac glycoside	Yes	Yes
Warfarin	Anticoagulant	Yes	Yes
Diazepam	Benzodiazepine	Yes	Yes
Clopidogrel	Anti-platelet	Yes	Yes
Cilostazol	Vasodilator	Yes	Yes
Rifampin St. John’s wort	CYP3A4 enzyme inducers	Yes	Yes
Tacrolimus	Immunosuppressant	Yes	Yes
Citalopram Sertraline	SSRI antidepressant	Yes	Yes
Phenytoin	Anticonvulsant	Yes	Yes

Warnings of Nexium and Prilosec

• Although the PPI may cause symptom relief, there could still be a malignancy. Consult your healthcare provider about the need for testing.
• Kidney problems may occur at any time. The PPI should be discontinued if kidney problems occur.
• PPIs can increase the risk of Clostridium difficile-associated diarrhea. Patients should take the lowest dose for the shortest duration of time.
• PPIs may be associated with bone fractures (hip, wrist, or spine). The risk is higher with higher doses, so patients should take the lowest dose of PPI for the shortest effective duration.
• Cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE) have been reported in patients taking PPIs.
• Long-term treatment (more than 3 years) may cause B-12 deficiency.
• Low magnesium (with or without symptoms) may occur. It is rare and usually occurs in patients who have taken a PPI for over a year. Consult your healthcare provider about monitoring magnesium levels.
• PPI use is associated with an increased risk of fundic gland polyps, and the risk increases with long-term use. Patients should take the PPI for the shortest duration possible.

Frequently asked questions about Nexium vs. Prilosec

What is Nexium?

Nexium, or esomeprazole, is a proton pump inhibitor (PPI) used to treat symptoms of acid reflux and other gastrointestinal (GI) conditions.

What is Prilosec?

Prilosec, or omeprazole, is a PPI used to treat symptoms of acid reflux and other GI conditions.

Are Nexium and Prilosec the same?

Nexium and Prilosec are in the drug class called proton pump inhibitors and are very similar. In fact, they are chemical isomers of each other. Other drugs in the PPI category you may have heard of include Aciphex (rabeprazole), Protonix (pantoprazole), and Prevacid (lansoprazole). PPIs are not to be confused with H2 blockers, another class of heartburn drugs used for GERD, which include Pepcid (famotidine).

Is Nexium or Prilosec better?

Both drugs are effective in treating GERD and other GI conditions. There are some studies (see above) that suggest Nexium may be more effective and work faster than Prilosec and other PPIs. However, both drugs remain very popular and are well-tolerated.

Can I use Nexium or Prilosec while pregnant?

There is not enough information to generally say if you can take Nexium or Prilosec while pregnant. Consult your OB-GYN whether it is safe to take Nexium or Prilosec if you are pregnant. If you are already taking one of these medications, and find out that you are pregnant, consult your OB-GYN for guidance.

Can I use Nexium or Prilosec with alcohol?

The medical information for Nexium and Prilosec does not specifically mention alcohol. However, alcohol may worsen the symptoms of GERD and other GI conditions. Consult your healthcare provider about whether or not you can drink alcohol with your medical condition(s).

What are the bad side effects of Nexium?

Nexium tends to be well-tolerated in most patients. The most common side effects of Nexium are headache, nausea, abdominal pain, and diarrhea.

Is Nexium safe to take everyday?

Nexium is taken every day (sometimes twice a day), and the length of treatment varies from 10 days to six months. However, some patients take it longer than six months based on the instructions from the healthcare provider.

Is Prilosec good for acid reflux?

Yes, Prilosec is a good option for acid reflux. In clinical studies, Prilosec helped to heal ulcers and improve symptoms.

What can I take instead of Nexium?

Other drugs in the same category of Nexium include Prilosec, Protonix, Prevacid, and Aciphex. Consult your healthcare provider for a recommendation if Nexium is not working for you.

In addition to taking a PPI or another medication for your symptoms, you can make dietary changes. Some foods that can help reduce acid are bananas, melon, whole grains, yogurt, lean proteins, and green vegetables (asparagus, kale, spinach, brussels sprouts).

Also, try to avoid foods that are fried, high in fat, or spicy. Other irritating foods and drinks to avoid include pineapples, citrus fruit/juices, tomatoes/tomato products, garlic, onions, alcohol, carbonated beverages, coffee, tea, chocolate, and mint. Keeping a food diary may help you to narrow down which foods and beverages help or hurt your symptoms.