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Diabetes

Digestive

Diarrhea

Diarrhoea is often caused by a stomach bug and usually settles within a few days. Learn how to prevent dehydration and when symptoms need medical advice.

Overview

Diarrhoea means passing loose or watery stools more often than usual. It is often caused by a stomach bug and usually gets better within a few days to a week. The main risk is dehydration.

How common is it?

Short-lived diarrhoea is very common in both adults and children.

Causes and risk factors

Common causes include viral gastroenteritis, food poisoning, some medicines such as antibiotics, food intolerance, and longer-term bowel conditions.

Common risk factors

  • Stomach bugs and contaminated food or water
  • Antibiotics
  • Travel
  • Being very young or older
  • A weakened immune system
  • Bowel conditions such as IBS or inflammatory bowel disease

Symptoms

  • Loose or watery stools
  • Tummy cramps
  • A sudden need to open your bowels
  • Nausea or vomiting
  • Fever
  • Blood or mucus in the stool in more serious cases
  • Signs of dehydration such as dark urine, dizziness, or a dry mouth

When to see a doctor

Get urgent medical advice if you or your child have signs of dehydration, bloody diarrhoea, cannot keep fluids down, or diarrhoea lasting more than 7 days. Call emergency services for severe tummy pain, vomiting blood, green vomit, a stiff neck, or pain in bright light.

Diagnosis

Most short-lived diarrhoea does not need tests. Stool tests, blood tests, or scans are usually reserved for symptoms that are severe, bloody, persistent, or linked to travel, immune problems, or another suspected cause.

Treatments

Oral rehydration

Sip water, diluted squash, soup, or oral rehydration sachets to replace fluid and salts. This is the most important treatment.

Food and rest

Eat small bland meals once you feel able, and rest while the illness is at its worst.

Medicines and other treatment

Loperamide can help some adults for a short time, but avoid it if you have blood in the stool, a high fever, or think you may have food poisoning. Antibiotics are only used for selected infections.

Self-care and lifestyle

  • Drink little and often to stay hydrated
  • Wash your hands well after using the toilet and before preparing food
  • Stay home from work or school until 48 hours after the last episode of diarrhoea or vomiting
  • Avoid alcohol until you are feeling better

Prevention

Hand hygiene, safe food preparation, and care with water and food while travelling reduce the risk of diarrhoea.

Sources and review

Last reviewed: 13 July 2026 by Living Diabetes Editorial Team. This guide was checked against current patient and professional guidance. It is educational and does not replace care from your own healthcare team.