Diarrhoea

Put simply, diarrhoea is when you pass loose, watery stools at a rate that is more frequent than what’s normal for you. It is very common and will affect most people in their lives. Fortunately, in most cases, although unpleasant, it isn’t anything to worry about. The most common cause of diarrhoea in both adults and children is gastroenteritis, which is a viral infection in the bowel.

Faeces can become loose and watery for various reasons. Anxiety, stress or emotional upset can cause the contents of the bowel to move through the digestive system too rapidly. This doesn’t allow the large intestine enough time to absorb the necessary fluid from the stools. A bacterial infection can cause what is known as secretory diarrhoea. This is where too much fluid is secreted into the bowel, diluting the stools consistency. If a virus or bacteria damages the lining of the digestive tract, it can result in the intestines being unable to absorb the fluid content within the bowel, resulting in watery stools.

Medicines can also cause diarrhoea as an unwanted side effect. Antibiotics, antacids, statins and laxatives are all common medicines that can cause diarrhoea. All the causes listed above usually only serve to induce diarrhoea for a short period of time. There are certain conditions that can result in more persistent long-term diarrhoea. These include bowel cancer, chronic pancreatitis, coeliac disease, Crohn’s disease, cystic fibrosis, ulcerative colitis and IBS (irritable bowel syndrome). 

The symptoms of diarrhoea are widespread. These symptoms will be dependent on the cause and who is affected. The most common symptoms will be watery stools, an upset stomach or cramps and an urgent, more frequent need to go to the toilet. Other common associated symptoms include; nausea and vomiting and loss of appetite. Whether you need to contact your doctor will depend on the severity of diarrhoea.

For adults it may become necessary to contact your GP if:

• Your diarrhoea has blood in it or you are experiencing bleeding from your rectum
• You are experiencing diarrhoea and have recently been in hospital
• Your diarrhoea has lasted longer than a week
• You are experiencing significant unexplained weight loss
• You have recently taken a course of antibiotics
• Your diarrhoea is persistent at night and is affecting your sleep
• The consistency is very watery and the amount and frequency is enough to cause dehydration
• Your diarrhoea and or vomiting is very persistent

Children with diarrhoea that lasts more than 24 hours should always see a doctor due to the increased risk of dehydration.

Diarrhoea can normally be self-diagnosed and treated in adults as long as you do not experience any of the symptoms listed above that would require further investigation by your doctor. Most cases resolve themselves within 3 to 5 days and only require treatment to relieve the symptoms. 

If your diarrhoea doesn’t get better of its own accord in around 3 days, then a visit to the doctor may be necessary. They will ask a series of questions to try to identify what’s causing the diarrhoea. These questions may include:

• Have you recently been abroad? (to rule out travellers’ diarrhoea)
• Have you recently dined out? (to rule out food poisoning)
• Have you been suffering with stress or anxiety recently?
• Are you experiencing any other symptoms?
• How often are you experiencing diarrhoea?
• Have you been in contact with anyone who has diarrhoea?
• What medication are you taking and has it recently changed?
• How much coffee and alcohol do you consume?

If your diarrhoea is persistent and has lasted for over a week, or if there are other symptoms, such as blood or puss in your stools, then your doctor may require a stool sample. This will provide a detailed analysis indicating what bacteria or parasites may be causing the diarrhoea. Other reasons why your doctor may request a stool sample include:

• If you have other symptoms that are affecting your whole body, such as dehydration or fever
• If you have a weakened immune system
• If you have recently returned from a trip abroad
• If you have recently been in hospital or have been taking antibiotics

If your doctor suspects there may be an underlying medical condition that could be causing your diarrhoea, for example, inflammatory bowel disease, then a blood test may be required. Doctors are also able to perform a physical exam by inserting a gloved finger into your anus and rectum. This will allow them to feel for any abnormalities. This rectal exam is an effective practice for diagnosing underlying conditions that affect the rectum and bowels. If the doctor is unable to find the cause of the diarrhoea then you may be referred to a hospital where further examinations can be performed. This will likely be a sigmoidoscopy or a colonoscopy, which are both flexible tubes with cameras and lights that can be inserted into the rectum and up into the bowel.   

Usually diarrhoea will resolve itself without the need for a ‘cure’ (such as antibiotics); the immune system will normally fight off the infection in just a few days. However, there are many ways to ease your symptoms during a bout of diarrhoea whilst the infection clears up.

Firstly, ensure you drink plenty of fluids to avoid dehydration. Your body loses a lot of fluids when suffering with diarrhoea and it is important to replenish these fluids. It’s recommended to take frequent yet small sips of water. If you are vomiting as well as having diarrhoea then it’s even more likely you will become dehydrated, making it even more important to replace the lost fluids from the body. Drinking fizzy drinks or fruit juices should be avoided as these can make diarrhoea worse. 

Oral rehydration sachets are designed to replace the glucose, salts and electrolytes as well as fluids that are lost from the body through dehydration. Rehydration sachets may help to ease diarrhoea and will help ensure there is less risk of dehydration and electrolyte loss. Dioralyte is a popular brand of rehydration treatment that comes in a variety of flavours.

You can also take antidiarrhoeals to ease your symptoms. This class of treatment is designed to shorten how long you suffer and also, decrease the amount of diarrhoea you experience. The most recognised and popular antidiarrhoeal drug is Loperamide, which is also known as Imodium. Loperamide reduces the movement of muscles in the gut, allowing for more water to be absorbed from the stools. The result, the stools have a more solid consistency and they are passed less often. Loperamide is also a popular choice as it produces very few side-effects. Loperamide should not be taken if blood or mucus is present in the stools or if the sufferer has a very high temperature or fever.

Alternatively, some people may prefer to treat their diarrhoea using probiotic supplements, such as Acidophilus or OptiBac, to amend the bacterial balance in their digestive tract.

In more serious cases of diarrhoea where it does not resolve with the over-the-counter treatment above or risk factors detailed above in ‘Symptoms’ become present, you should consult a doctor for further treatment and investigation.

Antibiotics may be recommended if the diarrhoea is severe and if the cause has been identified as a bacterial infection. Antibiotics are not suitable for treating diarrhoea if the cause is unknown. If a virus is to blame then antibiotics will be completely ineffective.

On rare occasions admittance to hospital may be required. This is usually when the sufferer has become severely dehydrated due to diarrhoea. Fluids and nutrients will be intravenously administers in order to rehydrate the patient. Using oral rehydration sachets can help to prevent this risk. 

Practising good hygiene is the best preventative measures when it comes to diarrhoea.  This will help prevent spreading the infection that causes diarrhoea. Always ensure to wash your hands thoroughly after using the toilet and prior to preparing or eating food. Regularly clean surfaces and utensils with hot, soapy water. When it comes to food, make sure you never store raw and cooked foods in the same place and ensure that all food is kept properly refrigerated. It’s important to cook your food thoroughly and never to eat it past the sell-by-date.

If you’re already experiencing diarrhoea and wish to reduce the risk of passing the infection on to others then there are steps you can take. For example, cleaning the toilet, including the seat and handle with disinfectant after each episode of diarrhoea. Try to avoid sharing towels, flannels, cutlery and utensils with other people. If suffering with diarrhoea it is recommended not to return to work or school until at least 48 hours after experiencing the last bout of diarrhoea.  

When travelling abroad there are certain preventative measures you can take to help avoid diarrhoea. See our Travellers' Diarrhoea section for more information.

Non-Prescription Alternatives

Imodium Capsules have provided a tried and trusted remedy for almost 40 years. The formula provides fast and effective relief from the symptoms of diarrhoea.

Dioralyte does not cure or treat diarrhoea. It will help to replace any fluids and electrolytes lost through diarrhoea; however it will have no curative effect.