What is gastroenteritis?

Gastroenteritis is the inflammation of the stomach and intestines, typically resulting in watery diarrhea, nausea, and vomiting. It is commonly referred to as the "stomach flu," though it is unrelated to influenza.

The most common causes include:

  • Viral infections

  • Contaminated food or water containing bacteria or parasites

  • Side effects from medications

Symptoms of gastroenteritis

People with gastroenteritis often experience the following symptoms:

  • Nausea and vomiting

  • Diarrhea

  • Abdominal cramps or belly pain

  • Occasional low-grade fever

First aid for adults

To manage symptoms and recover safely:

Sip liquids gradually
Avoid drinking large amounts quickly. Instead, take small, frequent sips of water, sports drinks, or rehydration solutions over several hours. This helps prevent dehydration without worsening nausea.

Monitor urination
Ensure regular urination with light-colored urine. Dark urine, dizziness, or lightheadedness may signal dehydration. If you can’t keep fluids down or show signs of dehydration, seek medical care.

Ease back into eating
Start with small amounts of bland foods like crackers, toast, rice, applesauce, bananas, gelatin, and skinless chicken. Avoid milk, dairy, alcohol, caffeine, spicy, or fatty foods until you fully recover.

Get rest
Rest is crucial as both illness and dehydration can make you feel extremely weak.

First aid for children

If your child has gastroenteritis, follow these steps:

Encourage rest
Let your child lie down and rest frequently.

Offer fluids slowly
Once vomiting stops, start giving small sips of an oral rehydration solution such as Pedialyte or Enfalyte. Do not rely solely on water or fruit juices like apple juice. If needed, use a water dropper or spoon instead of a bottle or cup to prevent gulping.

Introduce bland foods
Gradually add plain foods like bananas, rice, toast, and boiled potatoes. Avoid sweets, soda, and high-fat dairy such as whole milk and ice cream, which may worsen diarrhea.

Continue breastfeeding or bottle-feeding
If your baby is breastfeeding, continue to nurse. If bottle-fed, offer a small amount of rehydration solution or their usual formula.

When to see a doctor: adults

Seek medical attention if you experience any of the following:

  • Vomiting persists for more than 48 hours

  • Diarrhea continues for several days or becomes bloody

  • Fever is higher than 102°F (39°C)

  • You feel dizzy, lightheaded, or faint when standing

  • New confusion or severe abdominal pain develops

When to see a doctor: children

Call a healthcare provider if your child shows signs such as:

  • Unusual sleepiness or fatigue

  • Frequent vomiting or vomiting blood

  • Bloody diarrhea

  • Symptoms of dehydration: dry mouth, sunken eyes, no tears, or very dry diapers for more than 3 hours

  • For infants: sunken soft spot on the head

  • Any fever in infants

  • Fever above 102°F (39°C) in children over 3 months