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Common Diarrhoea Questions and Answers

Almost everyone has diarrhoea at some point, but not everyone knows why. With 40 years’ experience in treating diarrhoea, we've acquired a lot of knowledge about the condition - its causes, its symptoms and especially how to manage it.


These are the questions we're most often asked by our customers, along with our answers.

If you have a question about IMODIUM®, please read through our FAQs to see if you can find the answer before getting in touch.

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QA Question: 

Diarrhoea is a symptom of disruption to your digestive system, and you might be surprised how easy it is to tip the sensitive balance.

When your digestive system is in its normal rhythm, food and fluid pass regularly from the stomach into the small intestine. Food is then broken down and nutrients are absorbed along with most of the fluid. The remaining waste and some water pass into the colon (large intestine) where more water is absorbed and finally the waste is passed in the form of stools.

When your small intestine or colon are irritated, the relaxed and regular movement of your intestines can become overactive. Essential salts and fluids end up being passed through the colon too quickly with less fluid being absorbed by the body. The result is loose or watery stools, commonly known as diarrhoea.

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Several things can tip the balance of our sensitive digestive systems. For most people, it’s occasional, for example - a tummy bug or travel related. Others suffer more frequently and, for them, it can be changes in food (or drink) and mood (like stress) that trigger a bout of diarrhoea.

Here are some common factors that could cause diarrhoea:

  • Food eating habits and ‘trigger’ foods and drinks
  • Mood– stress, anxiety and nervousness
  • Irritable Bowel Syndrome
  • Food allergies and intolerances these are different but can both cause diarrhoea
  • Gastroenteritis inflammation of the stomach and intestines
  • Norovirus a viral infection that leads to gastroenteritis
  • Food poisoning ingestion of contaminated food or drink causing gastroenteritis
  • Menstruation many women react to their monthly hormonal changes
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Yes. According to a survey, 84% of us feel weak and tired when suffering from diarrhoea. This is no surprise when you consider the resulting loss of important fluids and salts from our body. So why leave it untreated when you can relieve diarrhoea?

IMODIUM® contains an active ingredient called Loperamide, which works with your body to help restore its natural rhythm, slowing digestion back down to a normal pace and renewing the absorption of fluids in your system.

Here’s what you can do if you get diarrhoea:

  • Stay hydrated by drinking plenty of fluids and/or taking a rehydration treatment
  • Take IMODIUM® straight after your first bout
  • Avoid fatty or spicy foods
  • As your appetite increases, eat small, light meals

If you have longer lasting or persistently recurrent diarrhoea, it might indicate an underlying medical condition, so you should talk to your doctor.

You should also see a doctor if:

  • Your symptoms last longer than 48 hours
  • You develop a fever over 38°C
  • You have blood or mucus in your stools

NHS Choices also recommends you should consult your GP if:

  • there is blood in your poo
  • you are vomiting persistently
  • you've lost a lot of weight
  • you have passed a large amount of very watery diarrhoea
  • it occurs at night and is disturbing your sleep
  • you have recently taken antibiotics or been treated in hospital
  • you have symptoms of dehydration
  • your poo is dark or black – this may be a sign of bleeding inside your stomach
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No. As a trusted diarrhoea treatment, IMODIUM® is widely available over the counter in chemists, as well as in supermarkets – whether you’re shopping online or on the high street.

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Many people believe that it’s best to let diarrhoea run its course so as to flush bacteria and toxins out of the body. But diarrhoea is not a defence mechanism. It’s a sign of disruption to the finely tuned machine that is our digestive system. It’s your immune system that fights infection, so there’s no need to leave diarrhoea to run its course. In fact, when left to run its course, diarrhoea can cause you to lose essential fluids and salts, leaving you feeling weak and depleted. Early treatment prevents this loss so you can feel better, than left untreated.

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As with many medicines, IMODIUM® is not recommended when you’re pregnant or breastfeeding. If you’re pregnant or caring for a newborn, diarrhoea can be the last thing you need. But, while you can’t use IMODIUM®, you can try to look after yourself by staying hydrated with oral rehyrdration therapy, drinking plenty of water, eating healthily and resting. If you’re concerned, it’s best to ask your GP for advice.

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IMODIUM® is suitable for children over 12 years of age, but not for younger children. Children can become dehydrated more quickly than adults, so oral hydration solutions are recommended.

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Oral rehydration solutions replace lost fluids and electrolytes, and help prevent dehydration but do not relieve the symptoms of diarrhoea. However, to help stop diarrhoea you can also use IMODIUM® together with an oral rehydration solution.

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IMODIUM® contains an active ingredient called Loperamide that works in harmony with your body to help restore its natural rhythm, gently slowing digestion back down to a normal pace. Contrary to popular belief, diarrhoea treatments like IMODIUM® don’t prevent stools from passing. When used correctly constipation is rarely a problem - in fact, in clinical trials with IMODIUM® less than 3% of users report constipation as a side effect. After a bout of diarrhoea you naturally feel empty and it can take time for your bowel to return to its normal pattern.

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IMODIUM®* can be used to treat diarrhoea associated with IBS in the UK, if it has been diagnosed by your doctor.

*Excluding IMODIUM® Plus Comfort Tablets

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Diarrhoea is a common health condition suffered by British tourists when abroad, and it can really upset your rhythm – not to mention your holiday.

Eating contaminated food and drinking contaminated water are the two most likely causes of travellers’ diarrhoea. It might also be caused by exposure to new types of bacteria – foreign bugs – that your body isn’t immune to, or simply by eating unfamiliar rich or spicy foods.

Don’t let diarrhoea spoil your trip - pack IMODIUM® before you travel for diarrhoea relief. IMODIUM® Instants are especially helpful if you’re on the go, as they dissolve on your tongue and you don’t need to take them with water.

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Overeating and drinking can upset your digestive system and lead to diarrhoea. So always try to eat sensibly and avoid excess. However if diarrhoea does occur, IMODIUM can quickly relieve the symptoms within one hour and can help you get your body back in harmony again.

Here are some everyday eating habits that can upset your digestive system:

  • Eating too quickly. It takes 20 minutes for your stomach to tell your brain it’s full, so eating more slowly means you’re likely to eat less and so have less to digest.
  • Gulping down food. When you gulp, you swallow air, which can lead to trapped wind and poor digestion.
  • Eating big, heavy meals. These take longer to digest and make your system work harder.
  • Eating late at night. Your digestive system is at its least efficient at the end of the day, so try to eat your last meal at least 3 hours before bedtime.
  • Eating too many fatty or spicy foods or drinking too much alcohol. These are common trigger foods, which can set off diarrhoea or worsen symptoms for people with IBS.
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When you get nervous, anxious or stressed, your body produces adrenaline and other chemicals, which speed up the function of your nervous system. This can make some of your muscles work faster than normal. If the muscles in your intestines speed up, the natural rhythm of your digestion will speed up too.

Faster digestion means your body absorbs less fluid, making your stools more frequent and watery - what we know as diarrhoea.

Just a small reduction in the fluid you absorb can be enough to bring on an attack of diarrhoea.

If you have a nerve-racking event coming up and you’re likely to have a problem, keep a pack of IMODIUM® with you and take them at the first sign of diarrhoea. IMODIUM® Instants are especially helpful if you’re out and about, as they dissolve on your tongue and you don’t need to take them with water.

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IMODIUM® Plus Comfort tablets work to quickly relieve diarrhoea within 1 hour, while also soothing painful cramps, uncomfortable bloating and embarrassing wind. They contain an additional ingredient called Simeticone, which helps to ease excess gas.

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About 1 in 5 women get diarrhoea during their period, more if they also have IBS. It can cause discomfort and make you feel self-conscious, but you don’t have to let it ruin your day. IMODIUM® can quickly help relieve diarrhoea during your period within 1 hour.

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If you’re someone who suffers from frequent diarrhoea, rest assured you’re not alone. A survey suggests that up to as many as one in ten people could suffer from diarrhoea on a frequent basis.

Diarrhoea is one of the most common complaints your pharmacist will deal with, and he or she is trained to offer you the best treatment possible. Remember, you can always ask to speak to your pharmacist in private.

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IMODIUM® Instants are specially made to dissolve instantly on your tongue, so you don’t need to swallow or use water. They simply melt and get to work, giving you fast and effective relief from diarrhoea – perfect if you’re on the go.

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You can find all our patient information leaflets (PILs) on the electronic Medicines Compendium at

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Everyone is different and it can be hard to identify the cause of your frequent diarrhoea. For some, it could be what they eat, say a trigger food or intolerance. For others, it might be a reaction to stress, anxiety or nervousness, while some people have diarrhoea related to IBS, when taking medication or during their period. It’s good to understand your body to help manage your diarrhoea accordingly.

Our Lifestyle & Wellbeing Tips section is full of advice on triggers of diarrhoea, improving digestive health and avoiding diarrhoea. If you have longer lasting or persistently recurrent diarrhoea, it might indicate an underlying medical condition, so you should consult your doctor.

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QA Question: 

Norovirus is one of the most common causes of viral gastrointestinal illness, which often leads to diarrhoea. Norovirus is very contagious and can spread quickly if you don’t wash your hands regularly. If you have diarrhoea as a result of norovirus, you can treat the symptoms with IMODIUM®.

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If this does not answer your question and you still wish to contact us, please click here.

If you need to report an adverse event or side effect from using one of our products, please call us on 01344 864 042.

There are many reasons why people get diarrhoea, from travelers’ diarrhoea and stomach bugs to IBS. Each one is different but they can all disrupt your life.

IMODIUM® works in harmony with your body to help restore its natural rhythm.

Exercise can enhance the way our digestive systems work and can even help shake off stress too.

IMODIUM® Original capsules can stop diarrhoea in one dose.


IMODIUM® IBS Relief helps you take control of your IBS diarrhoea.

IMODIUM® Instants dissolve instantly on your tongue, so they’re great for when you’re on the go.

IMODIUM® Plus Comfort tablets not only helps stop diarrhoea, but also soothe painful cramps, bloating and wind.

It’s easy to find IMODIUM® in supermarkets, chemists and many other shops. You don't need a prescription, so you can buy it over the counter as well as online.