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Travellers' diarrhoea


Traveller’s diarrhoea is a common condition that can affect people who travel abroad. It’s usually mild, but it can ruin a holiday. 

Symptoms of traveller’s diarrhoea include:

  • frequently passing watery stools (three or more a day)
  • stomach cramps
  • feeling or being sick

Read more about the symptoms of traveller’s diarrhoea.

Most cases of traveller’s diarrhoea are mild and should pass within three to five days without the need for medical treatment.

The most important thing to do is drink plenty of fluids, as diarrhoea can lead to dehydration.

If you need short-term relief from diarrhoea (for example because you’re going on a long journey), medication such as loperamide can stop you from going to the toilet. Loperamide is not suitable for children under the age of 12.

However, this type of treatment isn’t a cure and shouldn’t be used if you have a fever or blood in your stools.

In more severe or persistent cases, treatment with antibiotics may be required.

Read more about treating traveller’s diarrhoea.

In around 1 in 10 people, symptoms will last for up to two weeks. Occasionally, they can last for more than a month. Doctors refer to this as chronic diarrhoea and it is usually treated by a specialist in infectious diseases.

Causes of traveller's diarrhoea

Traveller’s diarrhoea is caused by consuming food or water that has been contaminated by bacteria, viruses or (less commonly) parasites.

This is most likely to happen in parts of the world where levels of hygiene and sanitation are poor, such as Central and South America and most of Asia, Africa and the Middle East. However, traveller's diarrhoea can happen anywhere.

Read more about the causes of traveller’s diarrhoea.


You can reduce your risk of traveller’s diarrhoea by taking some simple precautions when travelling, such as:

  • drinking only sealed bottle water
  • eating only food that has been thoroughly cooked and is very hot
  • boiling drinking water for at least one minute if you are unsure whether it is safe to drink

Read more about preventing traveller’s diarrhoea.

If you are particularly vulnerable to the effects of infection and you are travelling to a high-risk area, your GP may recommend you take antibiotics as a precaution against infection.

Vulnerable people include:

  • people with a weakened immune system, either due to a condition such as HIV or because they are receiving a treatment that weakens the immune system such as chemotherapy
  • very young and very old people
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Traveller's diarrhoea is usually described as passing three or more loose stools in one day, either while travelling or shortly after returning home.

Other symptoms include:

  • abdominal pain or cramps
  • being sick 
  • feeling sick

The symptoms of traveller's diarrhoea usually start within two to three days of arriving at your destination. Over 90% of cases occur within the first two weeks of a holiday or trip abroad. The symptoms usually get better without medical treatment within three to five days.

In around 1 in 10 travellers, the diarrhoea can last for two weeks or longer. In 1 in 100 travellers, the diarrhoea can last for longer than a month.

At-risk groups

Some people may be more at risk than others of developing complications from diarrhoea, such as dehydration. People who are most at risk include:

  • young children and babies
  • elderly or frail people
  • people with a weakened immune system, either due to a health condition or because they are receiving a treatment that weakens their immune system
  • people with heart disease, kidney disease or type 1 diabetes
  • people with inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis
  • people with reduced acidity in their stomach, such as those taking proton pump inhibitors to treat a stomach ulcer (reduced stomach acid can provide an environment in which some types of infection can thrive)

Symptoms of traveller's diarrhoea in these people may be more serious and should be monitored carefully.

When to seek medical attention

If someone, particularly a child, is dehydrated, see a doctor immediately. Signs of dehydration include:

  • irritability
  • restlessness
  • sunken eyes
  • dry skin
  • increased thirst

For more information about dehydration, read about the complications of traveller's diarrhoea.

Other signs that require medical attention include:

  • a high temperature (fever) of 38C (100.4F) or above
  • blood in the stools
  • finding it hard to keep enough fluid down because of frequently passing watery stools or repeatedly vomiting
  • diarrhoea that lasts longer than three to four days
  • diarrhoea that continues after you have taken antibiotics for three days

These symptoms could be the result of a more serious type of infection such as amoebic dysentery or giardiasis (both infections are caused by parasites).

Read more about how to get medical care abroad.

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Most cases of traveller’s diarrhoea are thought to be caused by eating food or drinking water that has been contaminated by bacteria, a virus or a parasite.

A wide range of organisms can cause traveller’s diarrhoea, including:

  • salmonella – bacteria found in raw meat and poultry and dairy products
  • campylobacter – bacteria found in raw meat and poultry, unpasteurised milk and unclean water
  • shigella – bacteria found in undercooked or raw food and spread through poor hygiene 
  • giardia intestinalis – a parasite found in contaminated water and spread through poor hygiene
  • cryptosporidium – a parasite found in contaminated food and water

High-risk foods

Food can become contaminated if:

  • it is handled by people who have not washed their hands after going to toilet
  • it is not properly cooked or refrigerated
  • cooked food is allowed to come into contact with raw food

Food that is most at risk of contamination includes:

  • raw seafood
  • undercooked meat or poultry
  • food from buffets, markets and street vendors
  • food from restaurants when you are uncertain if it has been properly cooked or refrigerated
  • food that contains raw or uncooked eggs (such as homemade mayonnaise)
  • unpeeled fruit and vegetables
  • ice cream

High-risk drinks

If you are travelling in a high-risk area for traveller’s diarrhoea, it is safer to assume that most sources of water, such as tap water, wells, rivers and lakes, are not safe to drink.

Stick to sealed bottled water, sealed fizzy drinks or drinks that you know have been boiled, such as tea and coffee.

Also, it is usually a good idea to avoid having ice in your drinks.

High-risk activities

Some types of holiday and activities increase your chances of having an episode of traveller's diarrhoea. For example, trekking or camping may increase your risk because you may not have access to clean water.

Being a passenger on a cruise ship also increases your risk. Poor hygiene could affect a large number of people, and being in close proximity to many others makes it easier for a virus or bacteria to spread.

High-risk areas of the world

A recent report from the Health Protection Agency summarised the potential risk of getting traveller’s diarrhoea depending on where in the world you were travelling to. They identified:

  • low-risk areas where your risk of getting traveller's diarrhoea is less than 1 in 14 – Western Europe, North America, Japan, Australia and New Zealand
  • medium-risk areas where your risk of getting traveller's diarrhoea could be as high as 1 in 5 – Eastern and Southern Europe, Russia, Israel, South Africa and some islands in the Caribbean
  • high-risk areas where your risk of getting traveller's diarrhoea is higher than 1 in 5 and could be as high as 1 in 2 – Africa, Central and South America, the Middle East and most of Asia
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Traveller's diarrhoea is easily diagnosed from the symptoms. In most cases, it will not require medical attention.

However, if you visit a GP or another healthcare professional while you are abroad, they are likely to ask you about some of the following:

  • how long you have had diarrhoea
  • how often you are going to the toilet
  • the consistency of your stools
  • if there is any blood in your stools
  • if you have any other symptoms
  • where you have been travelling

Stool sample

If you have other symptoms, such as blood in your stools or a fever, your GP or the healthcare professional treating you may want to run further tests. They may take a stool sample from you and test it in a laboratory to find out the cause of your diarrhoea.

If particular bacteria are responsible for your diarrhoea, the test results may help your GP work out which antibiotic medicine will be most effective at killing the bacteria.

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Traveller's diarrhoea should clear up without treatment in three to five days. The most important thing you can do is to drink enough fluid.

Medical attention is usually only required if you have more troublesome symptoms of traveller's diarrhoea. 

Drink plenty of fluid

Dehydration can be dangerous, particularly in young children, older people or those with existing medical conditions. If you have diarrhoea, make sure you drink plenty of sterile (clean) water or diluted fruit juice.

Drink two glasses of fluid each time you have a bowel movement and more if you feel thirsty. Take small, frequent sips and try to continue drinking even if you are vomiting.

Avoid drinking alcohol as this will make you more dehydrated.

If you are breastfeeding and your child has diarrhoea, continue to breastfeed them to ensure they do not get dehydrated.

Oral rehydration solutions

Oral rehydration solutions, such as Dioralyte or Electrolade, can be used by anyone who is at risk of dehydration. They are available in pharmacies and should be mixed with sterile water.

Oral rehydration solutions are not a treatment for diarrhoea. They are a way of getting fluid back into the body. They help replace the salt, glucose and other important minerals that you lose through diarrhoea.

Before using oral rehydration solutions, read the manufacturer’s instructions, particularly if you are giving them to young children.

Access to oral rehydration solutions can be limited in some parts of the world, so it may be a good idea to buy some before you travel.

Read more about the treatment of dehydration.

Eat as soon as you can

Once you feel able to, eat foods that are high in carbohydrates, such as bread, pasta, rice or potatoes. Eat small, light meals and avoid fatty, spicy or heavy foods.

When you feel like it, start to eat other foods. Salty foods, such as soup, can help replace the salt that has been lost from your system.

Not eating (if you feel too sick to eat) should not do you any harm, but continue to drink fluids and eat as soon as you can.


Some medications are available to help relieve diarrhoea, but avoid taking them if you can. Loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol) may be useful if the diarrhoea is particularly inconvenient, for example if you have a long journey to make.

These medications stop you from going to the toilet, which means that any bacteria or poisons are trapped in your body. They can also cause constipation and should not be used for more than one or two days.

Medications to help relieve diarrhoea are available over the counter in pharmacies across the UK. Always read the manufacturer’s instructions before using them.

Children aged under 12 should not use loperamide. Do not use it if you have an active inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis. It is not suitable if you have a fever or blood in your stools.

Children under 16 years of age should not use Pepto-Bismol. It should not be used if you have an allergy to aspirin. It is also not suitable if you are taking medication for gout or diabetes, or if you are taking an anticoagulant (blood-thinning medication) such as warfarin.


Antibiotics are usually only required if:

  • you have persistent symptoms of diarrhoea that are not responding to the treatments listed above and
  • testing shows that the cause of your symptoms is a bacterial infection

In the UK, antibiotics can only be prescribed by your GP. In some cases, you may be prescribed antibiotics to take with you when you go travelling (see preventing traveller’s diarrhoea). However, most people will need to seek medial attention abroad if they think antibiotics may be necessary.

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The main complication of traveller's diarrhoea is dehydration, where the normal water content of your body is reduced.

Symptoms of dehydration include:

  • increased thirst
  • irritability
  • restlessness
  • sunken eyes
  • dry skin, including the lips
  • dark, concentrated urine
  • dizziness or light-headedness

Get medical attention immediately if you or someone else is dehydrated.

Other medication

If you are taking other medication, diarrhoea may make it less effective. This is because the medication passes out of your body before it is absorbed, and so will not have any effect.

This can affect any medication. Take particular care if you are taking the oral contraceptive pill or the blood-thinning medicine (anticoagulant) warfarin.

If you take the oral contraceptive pill and have diarrhoea, it may not provide effective contraception because the pill will not have time to work before being passed out in your stools. This could lead to an unplanned pregnancy.

If you take warfarin and have diarrhoea, you may be at risk of blood clots forming inside your blood vessels. This can lead to serious complications, such as deep vein thrombosis (when a blood clot forms in one of the deep veins in your body) or a stroke (when a blood clot disrupts the blood supply to your brain).

Long-term diarrhoea

In some cases, traveller's diarrhoea may last for over a month while you are travelling abroad. If you are losing a lot of weight, seek medical attention. It may be worth changing your diet to see if this helps reduce your symptoms. You could try cutting out:

  • milk and dairy products
  • fatty, oily and spicy foods
  • alcohol

Long-term diarrhoea often gets better without treatment after you return home because you will no longer be exposed to the same bacteria and viruses that caused it.

In rare cases, long-term diarrhoea in travellers is due to another cause. The diarrhoea could be the start of another health problem that has nothing to do with your travels.

For example, diarrhoea can be a symptom of irritable bowel syndrome (IBS), which is a long-term disorder that affects the digestive system. IBS will require a full medical assessment by your GP.

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The wide range of different infections that can cause traveller’s diarrhoea means that it is hard to protect yourself with vaccination.

Before you leave

If you are planning a trip abroad, check the health advice for the country you are visiting. You can do this on the NHS Fit for Travel or National Travel Health Network and Centre websites. These can give you information about any travel vaccinations you may need, as well as advice about avoiding traveller's diarrhoea.

Make sure you have adequate travel insurance for the countries you are visiting. If you are travelling in Europe, you will need a European Health Insurance Card (EHIC), as well as travel insurance. An EHIC is free and could save you a lot of money and hassle if you need medical help while you are away.

If you have an increased risk of developing a serious complication from traveller’s diarrhoea, speak to your GP before you leave. They may be able to offer you additional advice about avoiding diarrhoea or may prescribe preventative antibiotics.

Preventative antibiotics

If you are in a high-risk group for developing serious complications from traveller’s diarrhoea, your GP may recommend you take antibiotics to protect yourself from infection.

If you're in a high-risk group, it may be recommended that you take antibiotics if you begin to get symptoms of traveller’s diarrhoea.

A widely used antibiotic for treating traveller’s diarrhoea is ciprofloxacin. A common side effect of ciprofloxacin is that it can make you feel sick, but this should pass with time.

Ciprofloxacin is not suitable for:

  • children and teenagers
  • pregnant women
  • people travelling to Southeast Asia or the Far East – this part of the world has high levels of resistance to ciprofloxacin, so it is much less effective (an alternative antibiotic called azithromycin can be used)

While you are away

Follow the advice below to prevent an episode of traveller's diarrhoea while you are away.

Water and ice precautions

  • Drink water only if you're sure it's sterile (clean).
  • If the water is not sterile, boil it for several minutes or use chemical disinfection or a reliable filter. This also applies to water that is used for making ice cubes, washing fruit or salad and for cleaning your teeth.
  • Avoid ice because it could be made with unclean water or it may have been touched by someone with dirty hands.
  • If you want a cold drink, pack ice around the outside of the glass or bottle.
  • Avoid drinks that are made with crushed ice, such as lassies (a drink made with crushed ice and yoghurt), as the ice may have been contaminated.
  • Bottled water and fizzy drinks are usually safe, but make sure the seal is not broken.

Food and drink precautions

  • Hot tea and coffee, beer and wine are usually safe.
  • If milk is pasteurised, it is safe. If you are not sure whether it is pasteurised, boil it first.
  • Yoghurt is usually safe.
  • Take care when buying cheese or ice cream. These are often made from unpasteurised milk so they may not be safe. Buy them from large, well-established companies as they are likely to be safer.
  • Food should be completely cooked and served piping hot. Once food reaches a temperature of over 60C (140F), any bacteria inside it will usually be killed.
  • Avoid eating leftovers or food that has been left out at room temperature.  
  • Fried rice is high risk because it is often made with "bits" that are lying around in the kitchen, and flash frying does not sterilise everything.
  • Food from markets and street vendors and some restaurants should be avoided unless the hot food has been kept hot and the cold food has been kept refrigerated or packed in ice.
  • Fish and shellfish can be hazardous at certain times of year, even if they are well cooked. Take local advice about seafood, but avoid it if in doubt.
  • Vegetables should only be eaten when they have been thoroughly cooked.
  • Avoid salads, unless you make them yourself, and wash everything in sterile water.
  • Fruit, including tomatoes, should be peeled.
  • Avoid smoothies because the fruit may have been contaminated when the smoothie was made.
  • If you are washing fruit to eat, the water needs to be sterile. Smooth-skinned fruit is easier to wash. Strawberries are very hard to clean. Avoid fruit that has split skin. 

Preventing the spread of infection

If you do develop traveller’s diarrhoea, it is important that you do not spread the infection to other people. The following advice should help:

  • Wash your hands thoroughly before eating or handling food and after using the toilet.
  • Dry your hands in the air or on a clean towel after washing them.
  • If possible, avoid preparing food for other people until your symptoms pass.
  • Short fingernails are easier to keep clean than long ones.
  • If you are going to be away from a source of running water for a significant amount of time, take a plastic bottle of soapy water and antiseptic wipes or a hand sanitiser with you.
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