Omeprazole
From £12.99
If you have been prescribed one of these medicines and are wondering about the other, the short answer is simple. Omeprazole and pantoprazole are different medicines from the same family. They are both proton pump inhibitors (PPIs) and are used for similar problems, including heartburn, acid reflux and some stomach ulcers.
At their usual doses, both can be effective at reducing stomach acid. The differences that matter are the dose, how each medicine is processed by the body, possible interactions with other medicines, and which one is more suitable for you. This guide explains those differences in plain English.
Key things to know
- They are different medicines in the same class, not the same medicine under two names
- Neither is automatically more effective than the other for everyday reflux and heartburn
- Pantoprazole 40mg and omeprazole 20mg are listed as standard dose equivalents in NICE guidance, so the milligram figures cannot be compared directly
- Pantoprazole has a lower potential for clinically important interactions with some medicines than omeprazole, which can matter when you take several medicines
- Pantoprazole 20mg can be bought from pharmacies for short term treatment of heartburn and acid reflux in adults. Omeprazole is also available without a prescription in some strengths and products, but the exact supply conditions depend on the product and pharmacist assessment.
Is Pantoprazole the Same as Omeprazole?
No. Whether the question is phrased as is pantoprazole the same as omeprazole, is omeprazole the same as pantoprazole, is omeprazole the same as pantoprazole, or are omeprazole and pantoprazole the same, the answer is the same. They are two different medicines.
What they share is their drug class. Both are proton pump inhibitors, alongside lansoprazole, esomeprazole and rabeprazole. PPIs reduce the amount of acid made by the stomach and are used for conditions such as acid reflux, GORD and some stomach ulcers.
That does not mean they should be taken together. Taking two PPIs at the same time is not normally necessary and can increase your exposure to medicine without providing an obvious extra benefit.
If you have been switched from omeprazole to pantoprazole, you have been given a different medicine. The dose is chosen according to the medicine and the reason you are taking it, rather than simply copying the number from one box to the other.
How They Work, and Why the Effect Builds Over Time
Both medicines reduce stomach acid by acting on the acid producing pumps in the stomach lining. They are generally taken before food, although the exact instructions depend on the medicine and product. Pantoprazole is usually taken about an hour before a meal.
You may start to feel some improvement within a few days, but these medicines are not designed to give the same immediate relief as an antacid. Pantoprazole, for example, can take up to 4 weeks to fully control symptoms.
If you have occasional breakthrough heartburn, an antacid or alginate may sometimes be used alongside pantoprazole. NHS guidance confirms that pantoprazole can be taken with an antacid such as Gaviscon. If you regularly need extra treatment, speak to a pharmacist or prescriber rather than adding medicines yourself.
What Is the Difference Between Omeprazole and Pantoprazole?
| Point of comparison | Omeprazole | Pantoprazole |
|---|---|---|
| Drug class | Proton pump inhibitor | Proton pump inhibitor |
| Common UK strengths | 10mg, 20mg, 40mg | 20mg, 40mg |
| Pharmacy availability | Some strengths and products are available from pharmacies | 20mg is available from pharmacies for short term heartburn and acid reflux in adults |
| Standard daily dose in NICE PPI comparison | 20mg | 40mg |
| Lower dose listed by NICE | 10mg | 20mg |
| Liver enzyme involvement | More interaction potential, particularly through CYP2C19 | Lower interaction potential than omeprazole for some medicines |
| Clopidogrel | Avoided with clopidogrel | Preferred over omeprazole when a PPI is needed with clopidogrel |
| Formulations | Capsules, tablets and other formulations depending on product | Gastro resistant tablets |
| UK brand names | Losec and other generic products | Pantoloc Control and other generic products |
| US brand names | Prilosec | Protonix |
NICE lists omeprazole 20mg and pantoprazole 40mg as standard PPI doses in its dose comparison. This is why a 20mg tablet or capsule of one medicine should not automatically be treated as equivalent to 20mg of another.
There is also an important interaction difference. Omeprazole has a clinically important interaction with clopidogrel, while pantoprazole is one of the PPIs that can be used in preference when a person taking clopidogrel needs a PPI.
The exact pharmacy availability also depends on the product. Pantoprazole 20mg is available from UK pharmacies for short term treatment of heartburn and acid reflux in adults. NHS guidance says it can usually be taken for up to 4 weeks when bought from a pharmacy, but you should speak to a doctor if symptoms have not improved after 2 weeks before taking more.
Omeprazole vs Pantoprazole: Which Is Stronger?
The question omeprazole vs pantoprazole which is stronger can be misleading because the milligram numbers are not directly comparable.
NICE uses the following standard PPI doses when comparing treatment doses:
| Proton pump inhibitor | Standard daily dose |
|---|---|
| Omeprazole | 20mg |
| Esomeprazole | 20mg |
| Rabeprazole | 20mg |
| Lansoprazole | 30mg |
| Pantoprazole | 40mg |
So, for this comparison, pantoprazole 40mg is considered a standard dose equivalent to omeprazole 20mg. That does not mean pantoprazole is simply twice as weak. Different medicines have different doses because their potency and pharmacology are different.
A 20mg pantoprazole tablet is therefore not automatically the same treatment as a 20mg omeprazole capsule. In fact, NICE lists pantoprazole 20mg as a lower dose and omeprazole 20mg as a standard dose in its PPI comparison.
This matters if you are switching between the two. If the new medicine does not seem to work in the same way, do not simply take an extra tablet. The prescriber or pharmacist can check whether the dose and treatment plan are appropriate for your condition.
Which Is Safer, Pantoprazole or Omeprazole?
There is no simple answer to which is safer overall. Both medicines belong to the same class, so they share many of the same possible side effects and long term considerations.
With longer term PPI treatment, possible issues can include:
- Low magnesium levels
- Vitamin B12 deficiency
- Certain gut infections
- Bone fractures, particularly with longer term use and other risk factors
- Rare kidney, liver or skin problems
The timing and frequency vary between these effects. For example, NHS guidance says that taking pantoprazole for more than 3 months may reduce magnesium levels, while taking it for more than a year may increase the chance of certain problems such as vitamin B12 deficiency, bone fractures and gut infections.
This does not mean that everyone taking a PPI will develop these problems. If you need long term treatment, your doctor can review whether you still need it and whether any monitoring is appropriate.
So, the better choice is often less about one medicine being universally safer and more about which medicine fits your other medicines, medical history and reason for treatment.
The Clopidogrel Interaction, Which Can Change the Choice
Clopidogrel is used to help prevent blood clots after conditions such as heart attacks, strokes and some procedures involving coronary stents.
It needs to be activated in the body by an enzyme called CYP2C19. Omeprazole and esomeprazole inhibit this enzyme and can reduce the amount of active clopidogrel. For this reason, NHS Specialist Pharmacy Service guidance recommends avoiding omeprazole and esomeprazole with clopidogrel. Pantoprazole, lansoprazole and rabeprazole are preferred alternatives when a PPI is needed.
Pantoprazole therefore has an advantage over omeprazole in this particular situation. That does not mean pantoprazole is automatically the better PPI for everyone.
If you take clopidogrel, do not change your PPI yourself. Your prescriber can choose an alternative if appropriate, while making sure your treatment for preventing blood clots continues.
Interactions to Declare Either Way
Both medicines can interact with other medicines, so it is worth giving your pharmacist or prescriber a complete list of what you take.
Depending on the medicine, this can include:
- Medicines used to prevent blood clots
- Warfarin
- Methotrexate
- Some HIV medicines
- Certain antifungal medicines
- Medicines that rely on stomach acid for absorption
Pantoprazole can also interact with medicines such as rifampicin and St John's wort. Omeprazole has its own list of interactions, including some medicines used for heart conditions, epilepsy and HIV.
If you take several prescription medicines, over the counter medicines, vitamins or herbal products, mention all of them before starting or switching a PPI.
Is Pantoprazole Better Than Omeprazole?
Not as a general rule.
Both medicines can be useful, and the right choice depends on why you need a PPI, what dose you need, how you respond to treatment and what other medicines you take.
Pantoprazole may be a better option when:
- You take clopidogrel and need a PPI
- Your prescriber wants to avoid some of the interactions associated with omeprazole
- Omeprazole has not suited you
- Pantoprazole is appropriate for the condition being treated
Omeprazole may be preferred when:
- Your prescriber wants to use one of the strengths or formulations available for omeprazole
- You are pregnant and a PPI is considered necessary, as omeprazole has more pregnancy safety information than other PPIs
- You have used omeprazole successfully before and there is no reason to change it
Pregnancy is a particularly important example. NHS guidance says omeprazole can usually be taken during pregnancy after checking with a pharmacist or doctor, while NHS guidance on pantoprazole says it is not usually recommended during pregnancy.
Pantoprazole Side Effects
Most people who take pantoprazole do not have side effects. When side effects do happen, they are usually mild. The official product information divides reported side effects into frequency groups, while NHS guidance gives a simpler patient focused list.
| Frequency | Reported effects |
|---|---|
| Very common | No very common side effects are listed |
| Common | Some product information lists certain effects in this category, but the exact list can vary by product |
| Uncommon, less than 1 in 100 | Headache, diarrhoea, nausea or vomiting, constipation, dry mouth, stomach pain or discomfort, bloating, dizziness, tiredness, sleep problems, rash or itching |
| Rare, less than 1 in 1,000 | More serious reactions can include severe allergic reactions, certain blood problems, liver problems and kidney inflammation |
| Very rare | Some serious blood disorders have been reported |
| Not known | Some reactions cannot be given a reliable frequency, including low magnesium or sodium, certain liver problems, microscopic colitis and some serious skin reactions |
The NHS specifically lists headache, diarrhoea, nausea or vomiting, constipation, dry mouth and tiredness as uncommon side effects, occurring in fewer than 1 in 100 people. Serious side effects are rare and occur in fewer than 1 in 1,000 people.
Seek medical advice promptly if you develop:
- A severe or blistering skin rash
- A rash with joint pain, particularly after exposure to sunlight
- Severe or persistent diarrhoea
- Yellowing of the skin or eyes, or dark urine
- Pain when passing urine, reduced urine output or swelling
- Muscle twitching, shaking or an irregular heartbeat, particularly during long term treatment
These symptoms do not necessarily mean pantoprazole is the cause, but they need medical assessment.
A severe allergic reaction needs emergency treatment. Call 999 if you develop sudden swelling of the lips, mouth, throat or tongue, serious difficulty breathing, or other signs of anaphylaxis.
Omeprazole has a broadly similar side effect profile because it belongs to the same medicine class. If a particular symptom continues after switching from one PPI to another, it is worth discussing it with your pharmacist or prescriber rather than assuming the new medicine is the solution.
If you have been taking a PPI for a long time, do not stop it suddenly without advice. NHS guidance notes that stopping long term pantoprazole suddenly can cause the stomach to produce more acid and make symptoms return. A gradual reduction may be recommended in some cases.
Protonix vs Omeprazole
Comparisons of Protonix vs omeprazole often come from American websites, which can make the names confusing.
Protonix is a brand name for pantoprazole in the United States. It is therefore the same medicine as pantoprazole, not a different medicine to compare with it.
Prilosec is a US brand name for omeprazole. Losec is a brand name used for omeprazole in the UK and other countries.
The important detail is the active ingredient rather than the brand name. If you are comparing a product bought in another country with a UK medicine, check the active ingredient and strength with a pharmacist rather than relying on the brand name alone.
Switching Between the Two
Switching from one PPI to another is something a prescriber can arrange when there is a good reason to change.
The dose is selected again rather than matched tablet for tablet because the strengths are not directly equivalent. NICE, for example, lists omeprazole 20mg and pantoprazole 40mg as standard doses in its PPI comparison.
You would not normally take both PPIs together unless a specialist has specifically instructed you to do so. If you have been told to switch, follow the new dosing instructions rather than adding the previous medicine as well.
It is also worth giving the new treatment enough time to work. Pantoprazole can begin improving symptoms within 2 to 3 days, although it can take up to 4 weeks to fully control symptoms.
If you have taken a PPI for a long time, ask your prescriber how to stop or reduce it. Some people can stop without tapering, while others may have a return of acid symptoms after stopping and may benefit from a planned reduction.
Getting Treatment in the UK
Short term heartburn and acid reflux can sometimes be managed with a pharmacy medicine and practical changes, such as avoiding meals close to bedtime and identifying foods or drinks that make your symptoms worse.
If you buy pantoprazole from a pharmacy, NHS guidance says not to take it for more than 4 weeks without speaking to a doctor. If your symptoms have not improved after 2 weeks, speak to a doctor before taking any more.
You should also speak to a GP if your symptoms keep returning or you have symptoms such as difficulty swallowing, unexplained weight loss, persistent vomiting, vomiting blood or black stools. These symptoms can have causes other than ordinary reflux and may need further assessment.
For ongoing treatment, an online consultation with a UK registered prescriber can help assess whether a PPI is appropriate and whether the dose and duration need to be reviewed. Where treatment is supplied, it should follow an appropriate clinical assessment rather than being treated as an open ended repeat.
Medical Disclaimer
This page compares omeprazole and pantoprazole in general terms. It is not personal medical advice and does not recommend a particular dose, product or treatment change for you.
Do not start, stop, switch or change the dose of a proton pump inhibitor without appropriate advice, particularly if you take clopidogrel or several other medicines. Speak to your GP, pharmacist or a UK registered prescriber about your individual circumstances.
If heartburn or acid reflux keeps coming back, it is worth finding out why rather than continuing to self treat indefinitely. Suspected side effects can be reported through the MHRA Yellow Card scheme.
