Sounds like 'low-PAIR-uh-mide'

Key points about loperamide

  • Loperamide is used to treat diarrhoea (runny poos).
  • Loperamide is also called Diamide Relief®, Diamide®, Diafix®, Gastro-stop®, Imodium®, Imodium Zapid®, Lorrex® or Nodia®.
  • Find out how to take it safely and possible side effects.
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Loperamide is used to treat diarrhoea (runny poos). It works by slowing the movement of the gut, and in this way reduces the number of bowel motions and firms up runny poos. Loperamide helps to ease diarrhoea but does not treat the cause of diarrhoea, such as infection or a tummy bug. Read more about diarrhoea. 

Loperamide is also used in people who have undergone an ileostomy (an operation that removed part of the bowel), to thicken your stool and reduce the amount of output from your ileostomy. 

In New Zealand, loperamide comes as capsules (2 mg) or tablets (2 mg) and orally disintegrating tablets (2 mg). It is available on prescription from your doctor or can be bought from your pharmacy without a prescription. 

  • The dose of loperamide will be different for different people, depending on your condition.
  • For sudden (acute) diarrhoea: take 4 mg( 2 tablets or capsules) to start, then  2 mg (1 tablet or capsule) after each time you go to the toilet with diarrhoea. Do not take more than 8 tablets or capsules in 24 hours. Stop taking loperamide as soon as the diarrhoea stops. If the diarrhoea continues for longer than 48 hours, contact your doctor.
  • For long-lasting (chronic) diarrhoea: start with 2 capsules or tablets daily and adjust your dose until you have 1 to 2 solid stools a day. The usual dose ranges from 2 to 12 mg daily (1 to 6 capsules or tablets daily). Do not take more than 8 tablets or capsules in 24 hours. 
  • If your doctor has prescribed loperamide, then take it exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much loperamide to take, how often to take it, and any special instructions.

  • Swallow the capsule or tablet with a glass of water. 
  • The orally disintegrating tablets (Imodium Zapid®) melt on your tongue without the need for water.
  • Loperamide can be taken before or after food. 
  • If you forget to take a dose, just take a dose after the next time you go to the toilet with diarrhoea. Do not take two doses together to make up for a missed dose.
  • Make sure you drink plenty of water or electrolyte replacement drinks because diarrhoea can make you dehydrated. Talk to your doctor or pharmacist about this.

  • Do have ulcerative colitis?
  • Do you have problems with your liver?
  • Are you pregnant or breastfeeding?
  • Do you have blood in your stools (poo) with a high fever?
  • Do you know if your diarrhoea has been caused by bacteria called Salmonella or Campylobacter or from antibiotic use?
  • Are you taking or using any other medicines? This includes any medicines being taken which are available to buy without a prescription, as well as herbal and complementary medicines.

If so, it’s important that you tell your doctor or pharmacist before taking loperamide. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

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

Side effects What should I do?
  • Constipation
  • Stop taking loperamide.
  • Tell your doctor if troublesome 
  • Gas, bloating, wind 
  • Headache
  • These are quite common when you take loperamide and usually goes away with time
  • Signs of obstruction of your bowels such as a feeling of tightness in your stomach, stomach cramps, problems with passing stools (poos) or gas, and vomiting
  • Stop taking loperamide.
  • Tell your doctor immediately or ring HealthLine 0800 611 116
Did you know that you can report a side effect to a medicine to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product(external link)

  • Loperamide may interact with a few medications and herbal supplements, so check with your doctor or pharmacist.
  • Check with our pharmacist before using over-the-counter medication such as laxatives (eg, Laxsol), or other diarrhoea medication (eg, Diastop). 

Loperamide(external link) New Zealand Formulary Patient Information

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Credits: Sandra Ponen, Pharmacist, Healthify He Puna Waiora. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Angela Lambie, Pharmacist, Auckland

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