Lansoprazole Vs Omeprazole: What's The Difference?

Acid reflux – also known as gastro-oesophageal reflux disease (GORD) – is one of the most common digestive conditions. It regularly causes heartburn, which affects one in four adults in the UK. Luckily there is a range of medications available to treat acid reflux, but which one is right for you?

In this article, we compare and contrast two common proton-pump inhibitor (PPI) drugs that are both regularly prescribed to treat acid reflux; lansoprazole and omeprazole.

What Is Omeprazole?

Omeprazole - also available under the brand names Losec, Losec MUPS and Pyrocalm in the UK – is an acid reflux treatment that falls into the PPI category of medicines. It works by reducing the amount of acid that your stomach produces, helping to treat acid reflux and prevent symptoms such as:

  • Heartburn
  • Oesophagitis (inflammation of your food pipe)
  • Bloating
  • Belching
  • Bad breath

Omeprazole is also effective in treating stomach ulcers, helping them to heal. PPIs such as omeprazole work by preventing the proton pumps in your stomach lining (enzymes which produce acid for food digestion) from working properly, limiting the amount of acid your stomach produces. Omeprazole contains omeprazole as its only active ingredient. The treatment is available in capsule, tablet and liquid form.

What Is Lansoprazole?

Like omeprazole, lansoprazole is an effective treatment for acid reflux or GORD, working to reduce symptoms such as:

  • Oesophagitis
  • Heartburn
  • Bloating
  • Bad breath
  • Stomach ulcers
  • Belching

Lansoprazole is a PPI that works in a similar way to omeprazole, reducing the amount of acid your stomach makes by inhibiting the proton pumps. Lansoprazole contains one active ingredient – lansoprazole – and is available under the brand name Zoton FasTabs in the UK. The treatment comes in capsules or tablets.

Omeprazole Dosage vs Lansoprazole Dosage

These two PPIs have different dosages, so let's compare them. Omeprazole comes in:

  • 10 mg capsules
  • 20 mg capsules
  • 40 mg capsules

For the treatment of acid reflux or GORD, a single 20 mg dose per day, taken before a meal, is usually recommended for adults. Children may be prescribed a dose of 5-20 mg, depending on their body weight.

Lansoprazole only comes in two doses:

  • 15 mg capsules
  • 30 mg capsules

The normal Lansoprazole dose to treat acid reflux or GORD for adults is 15-30 mg per day. Lansoprazole is taken 30 minutes before a meal. When taken once per day, lansoprazole is taken when you wake up in the morning. If you take it twice per day, you’ll take it once in the morning and once at night. Doses will be lower for children and older people.

How Long Does Omeprazole Take To Work?

It may take from a few days to a week for omeprazole to work. However, in some cases, people might need to take the treatment for months or even years. If you have bought omeprazole tablets from your local pharmacy, you may take it for up to two weeks to reduce acid reflux symptoms. If you don’t feel better after this time, you should inform your doctor. You may be switched to another medicine, or undergo tests to investigate the cause of your symptoms.

How Long Does Lansoprazole Take To Work?

After starting lansoprazole, you should begin to feel better within two to three days. In some cases, it could take up to four weeks for lansoprazole to work effectively, meaning you may experience acid reflux symptoms during this period.

You can stop taking lansoprazole once you feel better. However, some conditions can require lansoprazole to be taken for a few months or even years.

Omeprazole and lansoprazole are both able to improve acid reflux symptoms in a matter of days. However, some people will need to take the treatments for longer.

Omeprazole Interactions vs Lansoprazole Interactions

Several medicines may interact with omeprazole and lansoprazole, stopping either of the PPIs from working well or increasing your chances of side effects. These include:

  • Digoxin (the heart medicine)
  • Antifungal medicines like itraconazole, ketoconazole, posaconazole and voriconazole
  • HIV medicines
  • Methotrexate (a treatment for rheumatoid arthritis and psoriasis)
  • Rifampicin (the antibiotic)
  • Medicines to treat blood clots
  • Phenytoin (the epilepsy medicine)

Additionally, omeprazole may not mix well with cilostazol, a treatment for peripheral arterial disease (PAD), and lansoprazole may not mix well with fluvoxamine, the antidepressant.

The medicines included are not an exhaustive list of all the drugs that may not mix well with lansoprazole or omeprazole. You should refer to the information leaflet that comes with your medicine for a full list.

While omeprazole is safe to take during pregnancy, lansoprazole is not typically recommended, as there is less information regarding its safety for women and their pregnancies. For this reason, you are more likely to be given omeprazole when you are pregnant than lansoprazole. If your baby is healthy, both PPIs are usually OK to take when breastfeeding.

Omeprazole Side Effects

Not everyone will experience omeprazole side effects, however, there are some common potential side effects of omeprazole, which occur in more than one in 100 people. These side effects include:

  • Nausea
  • Vomiting
  • Diarrhoea
  • Stomach pain
  • Headache
  • Flatulence
  • Constipation

If you are concerned about any of these side effects, or they persist, ask your doctor for advice.

Serious side effects from omeprazole are rare. If you experience any of these side effects – which happen in less than one in 1,000 people – seek immediate medical help:

  • Jaundice (skin becoming yellow) and pee becoming darker
  • Joint pain accompanied by a red skin rash (this could be a symptom of a rare condition known as subacute cutaneous lupus erythematosus)
  • Severe or persistent diarrhoea

Lansoprazole Side Effects

As with omeprazole, not everyone will experience lansoprazole side effects. Common side effects shared with omeprazole, which can occur in more than one in 100 people, may include:

  • Nausea
  • Vomiting
  • Diarrhoea
  • Stomach pain
  • Headache
  • Flatulence
  • Constipation
  • Dizziness
  • Dry mouth

If these side effects persist, speak to your doctor.

Serious side effects from lansoprazole are rare. Lansoprazole shares these serious potential side effects – which happen in less than one in 1,000 people – with omeprazole:

  • Jaundice and pee becoming darker
  • Joint pain accompanied by a red skin rash
  • Severe or persistent diarrhoea

If you experience any of these side effects, seek immediate medical help.

What Are the Differences Between Omeprazole & Lansoprazole?

There are clearly many similarities between omeprazole and lansoprazole, however, there are some subtle differences.

Lansoprazole is understood to be the stronger and faster-acting of the two, meaning a lower dosage is typically needed. Omeprazole and lansoprazole also interact with other medicines in different ways. For example, a gap of an hour should be left between taking lansoprazole and an antacid such as Gaviscon, as the effectiveness of the PPI might be reduced. Furthermore, if you are pregnant, omeprazole is the more suitable treatment.

Omeprazole vs Lansoprazole: Which One Should I Buy?

Omeprazole and lansoprazole are both highly effective PPI treatments which treat the symptoms of acid reflux and GORD.

While both medications share many similarities, from how they work to what they treat, there are also several differences between the two; including their strength, their dosage, how fast they act, their interactions, and their suitability during pregnancy. The medication you should use will depend on which is more effective. For example, if you require a faster acting medication, lansoprazole may be more suitable, but if you are pregnant, we suggest purchasing omeprazole.

Talk to a medical professional to determine the best medication before you buy. Why not save time by purchasing omeprazole or lansoprazole online at Cloud Pharmacy? We offer both medications and provide next day delivery in the UK. Start your online consultation today.

Clinically Reviewed By:

Ibrahim Nakib BSc(Hons) MRPharmS