Gastroenteritis (Stomach Flu) | University of Portland

Gastroenteritis (Stomach Flu)

Although it's commonly called stomach flu, gastroenteritis isn't the same as influenza. Real flu (influenza) affects only your respiratory system—your nose, throat, and lungs. Gastroenteritis, on the other hand, attacks your intestines, causing signs and symptoms, such as:

  • Watery, usually nonbloody diarrhea (bloody diarrhea usually indicates a more severe infection)
  • Abdominal cramps and pain
  • Nausea, vomiting or both
  • Occasional muscle aches or headache
  • Low-grade fever

Viral gastroenteritis can spread when people eat or drink contaminated food or water, or if they share utensils, towels or food with someone who's infected.  Healthy people will likely recover without complications.

Depending on the cause, viral gastroenteritis symptoms may appear within one to three days after you're infected and can range from mild to severe. Symptoms usually last just a day or two, but occasionally they may persist as long as 10 days.

If you have gastroenteritis, the following self-care tips will help to ease symptoms:

  • Drink plenty of water to avoid dehydration
  • Take Tylenol for any fever or aches and pains
  • If you feel like eating, eat bland foods that are easy to digest like toast or soup
  • Stay comfortable at home to avoid transmission to others

When to see a medical provider if you have gastroenteritis:

  • You're not able to keep liquids down for 24 hours
  • You've been vomiting for more than two days
  • You're vomiting blood
  • You're dehydrated — signs of dehydration include excessive thirst, dry mouth, deep yellow urine or little or no urine, and severe weakness, dizziness or lightheadedness
  • You notice blood in your bowel movements
  • You have a fever above 104 F (40 C)

There's no effective treatment for viral gastroenteritis, so prevention is key. In addition to avoiding food and water that may be contaminated, thorough and frequent hand-washings are your best defense.  If you are ill, prevent the spread to others if you:

  • Stay home from class, work (especially if you work in food service) and other group activities while you are ill
  • Do not eat or prepare food with others while you are ill.  If you live on campus, perhaps a friend can deliver food to your room for you.
  • Wash your hands frequently.
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