Lansoprazole reduces the amount of acid in your stomach.
It treats:
- indigestion
- heartburn and acid reflux
- stomach ulcers
- a rare illness called Zollinger-Ellison syndrome
Lansoprazole comes as capsules and tablets that dissolve in water.
It is only available on prescription.
Brand names include:
- Lanzol
- Razolager
- Zomel
- Zoton FasTab
How lansoprazole works
Lansoprazole is a 'proton pump inhibitor' medicine that reduces acid in your stomach. It is different to an antacid. Proton pumps are tiny substances that make acid to digest food. Lansoprazole temporarily stops these pumps working.
Check if you can take lansoprazole
Lansoprazole can be taken by most adults. Children should only take lansoprazole if prescribed by a GP.
It may not be suitable if you:
- have ever had an allergic reaction to other medicines
- have liver problems
- are lactose intolerant
- are vegetarian, as capsules may contain gelatine
- have phenylketonuria (PKU) - FasTab contains aspartame
Ask your GP or pharmacist for advice before taking lansoprazole if:
- you're pregnant
- you think you may be pregnant
- you're trying for a baby
Pregnancy and lansoprazole
Lansoprazole is not recommended during pregnancy. There's no evidence it's safe while you are pregnant.
If you're pregnant, you may wish to treat your symptoms without taking lansoprazole. There are things you can try to prevent heartburn and acid reflux.
Your GP may recommend a different medicine to help with indigestion or too much stomach acid.
Breastfeeding and lansoprazole
If you are breastfeeding, ask your GP or pharmacist for advice before taking lansoprazole.
Lansoprazole may get into breast milk. But it's not known if it can harm your baby.
If you are breastfeeding, your GP may recommend a similar medicine instead. This may be a medicine that has more safety information available.
Contraception and fertility
Lansoprazole does not affect any type of regular contraception including the combined pill.
It may reduce the effectiveness of one type of emergency contraception called ellaOne (ulipristal).
Important
If using lansoprazole makes you sick (vomit) or you have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Check the pill packet to find out what to do.
There's no evidence that taking lansoprazole will reduce fertility in either men or women.
When you start taking lansoprazole
Always take this medicine exactly as your GP or pharmacist has described. Follow the advice on the label. If you're unsure, ask a GP or pharmacist.
You should start to feel better within 2 to 3 days.
It may take up to 4 weeks for lansoprazole to work properly. You may still have symptoms during this time.
The dose of your medicine depends on your condition. Your GP may increase or decrease your dose.
You may only need to take it for a few weeks or months. Some people need to take it for longer, even for many years.
How and when to take it
You usually take lansoprazole once a day in the morning.
For severe illness, you can take it 2 times a day - once in the morning and the evening.
Lansoprazole works best if you take it 30 minutes before a meal or snack. That's because food stops some lansoprazole getting into your system.
Swallow tablets and capsules whole with water or juice. If you have problems swallowing, open the capsules and mix the granules with water or juice. You can also sprinkle them onto soft food. Do not chew or crush the contents of the opened capsule.
Lansoprazole also comes as tablets that melt in your mouth if you cannot swallow pills.
Ask your GP or pharmacist for advice on how best to take lansoprazole if you're unsure.
If you forget to take it
If you take lansoprazole once a day, take the missed dose as soon as you remember. But if it is less than 12 hours until your next dose, skip the missed dose.
If you take it twice a day, take the missed dose as soon as you remember. But skip the missed dose if it is less than 4 hours until your next dose.
Do not take a double dose to make up for a forgotten dose.
If you take too much
Emergency action required: Go to your nearest emergency department (ED) or phone your GP if you take too much lansoprazole and:
- have flushed skin
- feel sweaty
- have a fast heartbeat
- feel sleepy
- have blurred vision
- feel confused or agitated
Bring the lansoprazole packet or leaflet and any remaining medicine with you.
Stopping treatment
Do not stop treatment early because your symptoms have got better.
You may not be fully better. Symptoms may come back if you do not finish your course of treatment.
Side effects
Most people who take lansoprazole do not have any side effects.
If you do have any, they are usually mild and go away when you stop taking it.
Talk to your GP or pharmacist if side effects get worse or do not go away after a few days.
Common side effects may include:
Headaches
Make sure you rest and drink fluids.
Ask your pharmacist to recommend a painkiller. Contact your GP if the headaches last longer than a week or are severe.
Feeling sick
It may help to not eat rich or spicy food while you're taking lansoprazole.
Diarrhoea or being sick (vomiting)
Drink lots of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee.
Do not take any other medicines to treat diarrhoea or vomiting without speaking to a pharmacist or GP. Contact your GP if diarrhoea or vomiting does not get better.
If you take the combined contraceptive pill or the progestogen-only pill and you are being sick (vomiting) or have severe diarrhoea for more than 24 hours, your contraception may not protect you from pregnancy. Check the pill packet for advice.
Stomach pain
Try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your stomach may also help. If you are in a lot of pain, speak to your pharmacist or GP.
Constipation
Try to eat more fibre, such as fresh fruit and vegetables and cereals. Drink plenty of water. Try to exercise regularly, for example by going for a daily walk or run.
If this does not help, talk to your pharmacist or GP.
Farting
Avoid foods that cause wind, like lentils, peas, beans and onions. It might also help to eat smaller and more frequent meals, eat and drink slowly, and exercise regularly. There are pharmacy medicines that can also help. Ask a pharmacist for advice.
Itchy skin rash
Try not to scratch your skin as this will make it worse. Hold something cool on your skin, like a damp towel. Have cool or warm baths or showers, but do not spend a long time in the bath or shower. Use an unperfumed moisturiser regularly.
Ask your pharmacist to recommend products to help with itchy skin, such as creams, lotions or antihistamines.
If the rash does not go away within a few days, speak to your pharmacist or GP.
Feeling dizzy
Stop what you're doing, and sit or lie down until you feel better. Do not drive or use tools or machinery until your dizziness has gone.
Dry mouth or throat
Chew sugar-free gum or suck sugar-free sweets.
Serious side effects
Urgent advice: Contact your GP straight away if:
- you have joint pain and a rash on skin exposed to the sun
- stomach pain that seems to be getting worse
- your skin is red, blisters or peels
- you have diarrhoea that does not get better
Serious allergic reaction
A serious allergic reaction (anaphylaxis) after taking lansoprazole is rare.
Emergency action required: Call 112 or 999 or go to your nearest emergency department (ED) if you:
- get a rash that's itchy, red, swollen or blistered
- are wheezing
- get tightness in your chest or throat
- have trouble breathing or talking
- have swelling in your mouth, face, lips, tongue or throat
Read the patient information leaflet that comes with your medicine for a full list of side effects.
Non-urgent advice: Find your patient information leaflet
Your patient information leaflet is the leaflet that comes with your medicine. You can find a digital version of the leaflet online.
Report side effects
You can report any suspected side effects to the Health Products Regulatory Authority (HPRA): report an issue - hpra.ie
Similar medicines
Talk to your GP if lansoprazole does not work or you have difficulty taking it. Your GP may suggest a different proton pump inhibitor.
Omeprazole, esomeprazole and pantoprazole are similar medicines. They are also available directly from pharmacies without a prescription.
Long-term use of lansoprazole
Levels of magnesium in your blood may fall if you take lansoprazole longer than 3 months.
This can make you feel tired, confused, dizzy and cause muscle twitches and an irregular heartbeat. Tell your GP if you get any of these symptoms.
Taking lansoprazole for more than 1 year can increase your chances of certain side effects, including:
- bone fractures, especially if you have osteoporosis
- bowel infections
- vitamin B12 deficiency
If you take lansoprazole for longer than 1 year your GP will regularly check your health. This is to see if you should carry on taking it.
People that take medicines that lower stomach acid, like lansoprazole, may have a very small chance of getting stomach cancer. This may be more likely in people who take them for longer than 3 years. But more evidence is needed.
Contact your GP if you notice any symptoms that may be signs of stomach cancer:
- problems swallowing (dysphagia)
- feeling or being sick
- feeling full very quickly when eating
- losing weight without trying
If you've taken lansoprazole for a long time speak to your GP before you stop. Stopping suddenly could make your stomach produce a lot more acid, and make your symptoms come back. Reducing the dose gradually before stopping completely will prevent this happening.
Taking lansoprazole with other medicines
Tell your GP or pharmacist that you are on lansoprazole before taking new medicines.
Check if you're already taking:
- digoxin (a heart medicine)
- antifungals such as itraconazole, ketoconazole or posaconazole
- methotrexate (for psoriasis and rheumatoid arthritis)
- HIV medicines
- theophylline (used to treat asthma)
- tacrolimus (used to prevent transplant rejection)
- phenytoin (an epilepsy medicine)
- rifampicin (an antibiotic)
- some blood thinners, for example warfarin
- fluvoxamine (an antidepressant)
Herbal remedies and supplements
Do not take St John's wort, the herbal remedy for depression, while you're taking lansoprazole.
St John's Wort may stop lansoprazole working as well as it should.
Tell your pharmacist or GP if you're taking herbal remedies, vitamins or supplements.
Other heartburn medicines
You can take lansoprazole with an antacid, for example Gaviscon. Antacids are medicines that counteract (neutralise) the acid in your stomach.
Take it 2 hours before or after your dose of lansoprazole.
Painkillers
It's safe to take painkillers such as paracetamol and ibuprofen at the same time as lansoprazole.
Talk to your GP or pharmacist before using ibuprofen as it can upset your stomach.
Food and drink
Avoid foods that make your symptoms worse, such as rich, spicy and fatty foods, and acidic foods like tomatoes, citrus fruits, salad dressings and fizzy drinks.
If you have symptoms at night, try not to eat for at least 3 hours before you go to bed.
Limit caffeinated drinks, such as tea, coffee and cola.
Alcohol does not affect the way lansoprazole works. But it's best not to drink too much alcohol. Alcohol makes your stomach produce more acid than normal. This can irritate your stomach lining and make your symptoms worse.
Fact check
This content was fact checked by a pharmacist, a GP, and the National Medication Safety Programme (Safermeds).
