Sounds like 'lan-so-pra-zol'

Easy-to-read medicine information about lansoprazole – what it is, how to take lansoprazole safely and possible side effects.

 Type of medicine

 Also called

  • Belongs to a group of medicines known as proton pump inhibitors
  • Solox®
  • Lanzol Relief®

What is lansoprazole?

  • Lansoprazole reduces the amount of acid produced in the stomach.
  • It is used to treat a number of stomach-related conditions caused by too much acid, such as indigestion, reflux, and ulcers.
  • It can also prevent ulcers from forming, or help the healing process where damage has already occurred.
  • Lansoprazole may be given (along with antibiotics) to get rid of Helicobacter pylori, a bacteria found in the stomach which can cause ulcers.
  • Lansoprazole may be used to prevent ulcers caused by medicines such as non-steroidal anti-inflammatory drugs (NSAIDs). Examples of NSAIDs are diclofenac, ibuprofen, naproxen.


  • The usual dose of lansoprazole is 30 mg once a day.
  • For some people, 15 mg once a day is enough.
  • Duration (how long you need to take it) varies from one week to many years.
  • If you have been taking lansoprazole for a year or more, ask your doctor if you could step down to an H2 blocker (such as ranitidine). Recent studies suggest there may be a number of risks from long-term use of proton pump inhibitors like lansoprazole including an increased risk of heart attacks, bone fractures and nutrient deficiencies such as low magnesium.

How to take lansoprazole

  • Take lansoprazole once a day at the same time each day, usually in the morning.
  • Swallow the capsule whole with a glass of water. Do not crush or chew - it does not work properly if the capsule is crushed or chewed.
  • If you find it difficult to swallow the capsule, you can open the capsule and sprinkle the contents on a small amount of soft food or liquid and swallow without chewing.
  • Do not crush the capsule contents.
  • Lansoprazole can be taken before or after food, although taking it 30 to 60 minutes before food is preferable.
  • If you forget to take your dose, take it as soon as you remember that day.
  • But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the amount.

Possible side effects

Like all medicines, lansoprazole can cause unwanted side effects, although not everyone gets them. Often unwanted side effects improve as your body adjusts to the new medicine.

Side effects What should I do?
  • Stomach upset, feeling sick
  • Feeling bloated, gas in the tummy
  • Loose stool (mild diarrhoea)
  • Constipation
  • These are quite common when you first start taking lansoprazole
  • Tell your doctor if troublesome 
  • Signs of low magnesium such as muscle cramps, weakness, tiredness, feeling irritable, and changes in heart beat
  • Increase your intake of magnesium-rich foods such as wholegrain cereals, green leafy vegetables (spinach, parsley, cabbage), peas, lean meats, nuts, seeds and bananas
  • Tell your doctor if troublesome — you may need a magnesium supplement
  • Severe diarrhoea (loose, watery, frequent stools)  
  • Lansoprazole can increase the chance of getting severe diarrhoea (which may be caused by a bacteria called clostridium difficle)
  • Stop lansoprazole and tell your doctor immediately 
  • Signs of an allergic reaction such as rash, fever, painful joints
  • Tell your doctor immediately or ring HealthLine 0800 611 116 
  • Worsening stomach problems such as really bad stomach pain, blood in the stool or black stools, vomit blood or dark coloured vomit.
  • Tell your doctor immediately or ring HealthLine 0800 611 116 


Lansoprazole may interact with a few medications and herbal supplements, so check with your doctor or pharmacist before starting lansoprazole or before starting any new medicines.

Learn more

Medsafe Consumer Information Sheet: Lanzol Relief

New Zealand Formulary Patient Information: lansoprazole

Credits: Sandra Ponen, Pharmacist. Reviewed By: Dr Janine Bycroft, Nov 2014