Traveller's diarrhoea — prevention and treatment
Reviewed by the My London Pharmacy clinical team, Yousef Yaghoubi, Pharmacist
·29 July 2026
·7 min read
Quick answer
Traveller's diarrhoea is a common gut upset caught abroad, usually from contaminated food or water. Most cases are mild and settle within a few days. Careful food and water hygiene lowers your risk, and staying well hydrated is the priority if you do become unwell.
What traveller's diarrhoea is
Traveller's diarrhoea is the most common illness affecting people who travel, particularly to parts of Africa, Asia, the Middle East and Central and South America. It usually develops in the first week or two of a trip and is most often caused by bacteria picked up from contaminated food or water, though viruses and parasites can also be responsible. The change in local bugs, food handling and water supply is what catches many travellers out, even those who are careful.
The illness is typically defined as passing three or more loose or watery stools in a day, often alongside stomach cramps. While it is unpleasant and can disrupt a trip, most cases are mild, self-limiting and clear up on their own within three to five days. Understanding how it spreads, how to lower your risk, and how to look after yourself if you do become unwell can make a real difference to how much it affects your travels.
Symptoms and how it usually progresses
Symptoms tend to come on suddenly, sometimes within hours of eating something contaminated. They can include:
- Loose or watery stools, often several times a day
- Stomach cramps, bloating and an unsettled feeling
- Nausea, and sometimes vomiting
- An urgent need to reach a toilet
- A mild fever and a general feeling of being unwell in some cases
For most people the illness eases within a few days as the body clears the infection naturally. The main risk during this time is dehydration, which happens when you lose more fluid than you take in. This is especially likely in hot climates, and it can develop more quickly in young children, older adults and anyone with a long-term health condition. Because of this, replacing lost fluids is the single most important part of looking after yourself, even more so than trying to stop the diarrhoea itself.
How to reduce your risk
Careful attention to what you eat and drink is the best way to lower your chances of becoming unwell. No approach removes the risk entirely, but sensible precautions make a genuine difference. These include:
- Drink safe water. Choose sealed bottled water, or water that has been boiled or properly treated, and use it for brushing your teeth in higher-risk areas.
- Avoid ice unless you know it was made with safe water, as frozen water carries the same risks as unsafe drinking water.
- Eat food that is freshly cooked and served piping hot. Be cautious with buffets, food left standing at room temperature, and raw or undercooked meat, fish and shellfish.
- Peel fruit and vegetables yourself, and be wary of salads and raw items that may have been washed in untreated water.
- Be careful with dairy that may not have been pasteurised or kept properly chilled.
- Wash your hands regularly with soap and safe water, or use an alcohol-based sanitiser, before eating and after using the toilet.
Following the familiar guidance to boil it, cook it, peel it or leave it is a useful rule of thumb for higher-risk destinations, and it becomes second nature after the first few days of a trip.
Managing symptoms if you become unwell
The cornerstone of treatment is keeping well hydrated. Drink plenty of safe fluids to replace what you are losing through diarrhoea and any vomiting, sipping little and often if your stomach feels delicate. Oral rehydration salts, which restore the balance of water and minerals your body needs, are particularly valuable and are simple to carry in your luggage. They are especially useful for children and older travellers, who become dehydrated more easily.
Rest where you can, and reintroduce plain, easily digested foods such as bread, rice, bananas or plain crackers as your appetite returns, rather than forcing rich or spicy meals too soon. Many people manage a mild episode with hydration and rest alone. Anti-diarrhoeal medicines can reduce the number of times you need the toilet and may be helpful for essential travel, such as a long coach or plane journey, but they are not suitable for everyone. In particular, they are best avoided if you have a high fever or notice blood in your stools, as slowing the gut can sometimes be unhelpful in these situations. A pharmacist can advise on what is appropriate for you, ideally before you travel so you are prepared.
In more significant cases, a clinician may consider whether other treatment is needed. This depends on your symptoms, your destination and your medical history, so it is best discussed as part of a consultation rather than assumed.
Travellers who need extra care
While traveller's diarrhoea is usually mild, some people need to take particular care because they are more vulnerable to dehydration or complications. This includes babies and young children, older adults, people who are pregnant, and anyone with a weakened immune system or a long-term condition such as diabetes, inflammatory bowel disease or kidney problems.
For these travellers, it is worth being especially vigilant about food and water hygiene, carrying oral rehydration salts, and seeking advice sooner rather than later if symptoms develop. If you fall into one of these groups, or you are travelling with someone who does, a conversation with a pharmacist before your trip can help you plan what to pack and what to watch out for, so you feel confident managing any illness that arises.
When to seek medical help
Most episodes settle without the need to see a doctor, but you should seek medical advice if you notice any of the following:
- Blood or mucus in your stools
- A high fever
- Severe or persistent vomiting that stops you keeping fluids down
- Signs of dehydration, such as feeling very thirsty, a dry mouth, passing little urine, or dizziness
- Severe stomach pain
- Symptoms lasting longer than a few days, or diarrhoea that continues after you return home
Seek help sooner for young children, older adults, people who are pregnant and anyone with a weakened immune system or a long-term health condition, as dehydration can develop more quickly and become more serious in these groups. Diarrhoea that persists after you get back to the UK is also worth mentioning to a clinician, as it occasionally points to an infection that needs specific investigation.
If symptoms continue after you return
Most travellers recover fully within a few days, but occasionally diarrhoea persists after you get home, or begins only once you are back in the UK. This can happen when an infection lingers or when a less common cause, such as a parasite, is involved. Ongoing symptoms are worth taking seriously rather than simply waiting out, particularly if they drag on for more than a week or keep returning.
If you experience persistent or recurring diarrhoea after travelling, it is sensible to speak to a clinician and mention where you have been, when, and how long you were away. This helps guide whether any specific investigation, such as a stool sample, would be useful. Keeping a note of your symptoms, their timing and any foods that seem to trigger them can also help. Prompt advice means any underlying cause can be identified and managed, so you can get back to feeling yourself rather than living with unexplained gut symptoms for weeks after your trip has ended.
Planning ahead before you travel
A little preparation goes a long way. Before a trip to a higher-risk destination, it can help to pack oral rehydration salts, a hand sanitiser, and a small supply of any regular medicines you take, keeping them in your hand luggage in case of delays. Thinking through where you will find safe food and water also makes it easier to stay well once you arrive.
If you have an upcoming trip and want tailored advice on staying healthy abroad, the My London Pharmacy team can talk through your destination, your plans and your circumstances, and help you prepare with confidence so that a common gut upset does not overshadow your travels.
Frequently asked questions
How long does traveller's diarrhoea last?
Most cases are mild and clear up on their own within three to five days. The priority throughout is staying well hydrated, particularly in hot climates.
What is the most important thing to do if I get it?
Replacing lost fluids is the key. Drink plenty of safe water and consider oral rehydration salts, which are especially useful for children and older travellers.
How can I avoid it in the first place?
Careful food and water hygiene lowers your risk: drink sealed or treated water, avoid ice of unknown origin, eat freshly cooked hot food, and wash your hands regularly.
Are anti-diarrhoeal medicines safe to use?
They can reduce symptoms for essential travel but are not right for everyone, and are best avoided if you have a high fever or blood in your stools. Ask a pharmacist for advice before you travel.
When should I see a doctor?
Seek help if you have blood in your stools, a high fever, severe vomiting, signs of dehydration, or symptoms that last more than a few days, and sooner for young children and older adults.
What should I eat while recovering?
Once your appetite returns, start with plain, easily digested foods such as bread, rice, bananas or crackers, and keep sipping fluids rather than jumping straight back to rich or spicy meals.