Diarrhoea & Vomiting:
Causes, Self-Care

The most common cause is gastroenteritis — inflammation of the stomach and bowel. This is usually triggered by:

• Viruses such as norovirus (the "winter vomiting bug") or, in young children, rotavirus
• Food poisoning from bacteria such as salmonella or campylobacter, or from contaminated food or water
• Medication side effects, such as those from antibiotics
• Contaminated water or food while travelling abroad

In a typical bout of gastroenteritis, vomiting usually settles within one to two days. Diarrhoea tends to last a little longer, often around five to seven days. You may feel washed out for a few days afterwards, even once the main symptoms pass.

Symptoms that last longer than this, or that keep returning, are a signal to be seen.

Most mild cases can be managed safely with simple self-care.

• Stay hydrated. Take small sips if you feel sick, rather than large gulps. Oral rehydration solutions from the pharmacy replace lost salts as well as fluid, and work better than water alone.
• Eat when you feel able to. There is no need to starve yourself. Bland foods such as toast, rice, and bananas, eaten little and often, are usually easier to tolerate.
• Avoid foods and drinks that irritate the stomach. Avoid spicy food, fatty food, caffeine, and undiluted fruit juice until symptoms settle. Avoid alcohol completely while you are unwell.
• Manage fever and aches. Paracetamol can help, used as directed on the packet.
• Rest, and let the illness run its course.
• Wash your hands thoroughly and often. Tummy bugs spread very easily through households.
• Stay off work, and keep children off school or nursery, until 48 hours after the last episode of diarrhoea or vomiting.

Dehydration is the main risk with any tummy bug, particularly for babies, young children, and older adults. Watch for:

• A dry mouth and lips, or feeling very thirsty
• Dark yellow, strong-smelling urine, or passing much less than usual
• Dizziness or light-headedness, especially on standing
• Tiredness that feels out of proportion
• In babies: fewer wet nappies, a sunken soft spot, crying with few tears, or unusual drowsiness

Arrange a medical assessment if:

• You cannot keep fluids down for more than 24 hours
• There is blood in your stool, or vomit that looks like coffee grounds
• Vomiting has lasted more than two days, or diarrhoea more than a week
• You have severe or constant abdominal pain
• You have a high fever that is not settling
• Symptoms began during or after travel abroad
• The person affected is a baby, an older adult, pregnant, or has a weakened immune system or other significant medical condition
• Symptoms keep recurring, or your bowels have not returned to normal

Children pick up gastroenteritis more often than anyone else. Nurseries and schools pass bugs around efficiently, and children dehydrate more quickly than adults.

With little ones, focus on small, frequent sips of fluid rather than large amounts at once. An oral rehydration solution is better than water alone for anything more than a mild bout. Keep an eye on wet nappies and alertness rather than appetite — appetite is always the last thing to return, and that is normal.

Have a child seen the same day if they are under one with repeated vomiting or diarrhoea. The same applies if they show any signs of dehydration, refuse all fluids, seem unusually drowsy or floppy, or have blood in their stool. If your instinct says a child needs checking, that is reason enough on its own.

Gastroenteritis is highly contagious, and one family member unwell often becomes several. To limit the spread:

• Wash hands with soap and water — alcohol gel is far less effective against norovirus
• Give the unwell person their own towel, and wash bedding and towels on a hot wash
• Clean bathrooms and door handles regularly with a bleach-based cleaner
• Keep the unwell person away from food preparation entirely until 48 hours symptom-free

Usually, no. Most gastroenteritis is viral, and antibiotics have no effect on viruses. Even many bacterial tummy bugs settle on their own. Antibiotics are only used in specific situations, usually guided by a stool test.

This is a judgement a clinician makes with you, based on your symptoms, your medical history, and, where recommended, test results.

A clinician will ask about your symptoms and medical history. This includes when they started, how often they occur, any recent travel, and your general health.

They will examine you and check for signs of dehydration. Depending on the findings, they may arrange:

• A stool or urine sample, to identify an infection
• Blood tests, to check for dehydration, infection, or inflammation
• Fluids given directly, if oral rehydration is not effective

People across Milton Keynes and nearby areas - including Bletchley, Newport Pagnell, Stony Stratford, Bedford, Buckingham, and Leighton Buzzard — can be assessed locally, the same day.

At Bloom Health's Walk-In Centre, the centre is open from 8am to 10pm, seven days a week, with no appointment or referral needed. You will be seen by experienced GPs and A&E consultants, and the team assesses adults and children from birth.

If a tummy bug is dragging on, or you are worried about dehydration — particularly in a child — walk in, or call the team on 01908 227777.

For severe abdominal pain, vomit that looks like coffee grounds, or signs of severe dehydration, call 999 or go to A&E immediately. For urgent advice when you are unsure what to do, contact NHS 111.