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A young woman snacks on a plate of assorted fruits to help improve her digestive health.

What is gastroenteritis?

Gastroenteritis—also known as stomach flu or gastric flu—is a condition characterized by inflammation of the gastrointestinal tract, which includes the stomach and intestines. It is usually caused by a viral or bacterial infection, although parasites, toxins, or other agents can also cause it.

What are the risk factors for gastroenteritis?

Several risk factors can increase the likelihood of developing gastroenteritis, including:

  • Age: Infants, young children, and seniors are more susceptible to gastroenteritis due to their weaker immune systems.
  • Weakened immune system: People with weakened immune systems due to medical conditions such as HIV/AIDS or cancer, or as a result of medications that suppress the immune system, are at a higher risk of developing gastroenteritis.
  • Contact with infected individuals: Gastroenteritis can be highly contagious, and close contact with someone who is infected can increase the risk of contracting the illness.
  • Poor hygiene: Poor hygiene practices, such as not washing hands after using the bathroom or before handling food, can increase the risk of gastroenteritis.
  • Consumption of contaminated food or water: Eating or drinking food or water that is contaminated with bacteria or viruses can lead to gastroenteritis.
  • Travel: Traveling to areas with poor sanitation or hygiene practices can increase the risk of gastroenteritis.
  • Crowded living conditions: People who live in overcrowded or unsanitary conditions, such as nursing homes or prisons, are at a higher risk of gastroenteritis.

What are the symptoms of gastroenteritis?

  • Nausea and vomiting
  • Diarrhea
  • Abdominal pain or cramping
  • Loss of appetite
  • Fever
  • Headache
  • Dehydration
  • Muscle aches or weakness

Symptoms of gastroenteritis usually appear within one to three days after exposure to the virus or bacteria and can last for several days to a week or more. In some cases, symptoms may also include bloody stools or severe abdominal pain, which can indicate a more serious condition and require immediate medical attention.

If you are experiencing any of these symptoms, schedule an appointment with a primary care provider today.

How do you diagnose gastroenteritis?

A provider will diagnose gastroenteritis through a physical exam, medical history, and symptoms. In some cases, a radiologist may perform laboratory tests to confirm the diagnosis and rule out other conditions.

During a physical exam, a primary care provider may check for signs of dehydration, such as dry mouth or skin, and abdominal tenderness or bloating. They may also ask about recent travel, food or water consumption, and contact with sick individuals.

A provider may use the following lab tests to diagnose gastroenteritis:

  • A stool sample may be collected and sent to a laboratory to test for the presence of bacteria, viruses, or parasites.
  • Blood tests can help identify signs of infection, dehydration, and other abnormalities.
  • Imaging tests such as X-rays or CT scans may be used to rule out other conditions or complications.

What are the steps for treating gastroenteritis?

The treatment of gastroenteritis usually involves supportive care to manage symptoms and prevent complications. In most cases, the illness resolves on its own within a few days to a week. Here are some common treatments for gastroenteritis:

  • Hydration: It's essential to stay hydrated during gastroenteritis to replace fluids and electrolytes lost due to vomiting and diarrhea. Drink plenty of water, clear broths, or electrolyte-rich fluids like sports drinks, coconut water, or oral rehydration solutions.
  • Rest: Rest can help conserve energy and reduce symptoms of nausea, vomiting, and abdominal pain.
  • Medications: Over-the-counter medications such as antidiarrheals and antacids may help reduce symptoms of diarrhea and stomach pain. However, it's essential to check with a primary care provider before taking any medications, especially in young children, pregnant women, or people with underlying health conditions.
  • Diet: A bland diet of plain toast, crackers, bananas, and rice, known as the BRAT diet, may help ease symptoms of gastroenteritis. Avoid caffeine, dairy products, spicy foods, and alcohol.
  • Antibiotics: Antibiotics are only effective if the gastroenteritis is caused by bacteria. Viral gastroenteritis doesn't respond to antibiotics, and overuse of antibiotics can lead to antibiotic resistance.

Our experienced, board-certified gastroenterologists serve patients throughout the Greater Houston area. No matter where you live or which location you choose, you can trust that we will provide the same patient-centered standards of quality care to everyone.

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