Dr. Niamh Kelly
In personOnlineIMC verified
Diarrhoea
Diarrhoea means passing loose or watery stool more often than usual. It is often caused by infection or unsafe food or water, and the main danger is dehydration.
When to get emergency care
Get emergency help immediately if you have any of these:
- Signs of dehydration such as very little urine, extreme thirst, dry mouth, sunken eyes, dizziness or drowsiness.
- Blood in stool, black stool, or severe rectal bleeding.
- Diarrhoea with severe abdominal pain, swollen belly, high fever or confusion.
- Repeated vomiting or inability to keep fluids down.
- Diarrhoea in a baby, older adult, pregnant person, or someone with diabetes, kidney disease or weak immunity.
Get emergency help or call 112
Common causes
- Viral or bacterial infection from contaminated food or water.
- Food poisoning during travel or eating outside.
- Infections picked up while travelling abroad.
- Reaction to medicines or antibiotics.
- Longer-term bowel conditions if symptoms keep returning.
What to expect at your consultation
- A clinician may ask about stool frequency, blood, fever, vomiting, travel, food and water exposure.
- They may check hydration, pulse and blood pressure.
- Stool tests or blood tests may be needed if symptoms are severe, persistent or bloody.
Looking after yourself
- Sip safe fluids often if you can keep them down.
- Eat simple foods when you feel able and avoid unsafe water or uncovered food.
- Seek care promptly if there are dehydration signs, blood or high fever.
Frequently asked questions
- Why is dehydration important in diarrhoea?
- Loose stools can quickly reduce body fluids and salts, especially in children and older adults.
- Is blood in stool normal with diarrhoea?
- No. Blood or black stool should be checked urgently.
- Can unsafe water cause diarrhoea?
- Yes. Contaminated water is a common cause of diarrhoea and stomach infection.
- When should a child with diarrhoea be seen?
- Urgent care is needed if the child is very thirsty, drowsy, passing little urine, has blood in stool, or cannot keep fluids down.
Not sure how urgent this is?
Answer a few questions and we will tell you how soon to be seen.
Check my symptomsWhich doctor should I see?
- General Physician Can assess dehydration and common infections.
- Gastroenterologist Helpful for persistent, bloody or recurrent diarrhoea.
Not sure? See a general physician
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Dr. Ronan Fitzgerald
In personOnlineIMC verified
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