Symptoms of the Stomach Flu

In This Article

Viral gastroenteritis, commonly known as the stomach flu or stomach bug, is a highly contagious illness that causes vomiting, diarrhea, abdominal pain, and weakness, among other possible and very uncomfortable symptoms. For most, it is short-lived and without consequence. However, it's worth monitoring for symptoms of dehydration, such as dizziness and thirst, as excessive fluid loss can occur as the result of the stomach flu; this is of particular concern for children, seniors, and those who are immunocompromised.

Despite its nickname, the stomach flu is not one of the influenza viruses (which are characterized by respiratory symptoms instead of gastrointestinal ones).

Stomach Flu - Common Symptoms
Verywell / JR Bee

Frequent Symptoms

Typically, the stomach flu is a "self-limiting" illness, which means it will go away on its own after a few days.

In some cases, bacterial infections may hang on longer and need to be treated with antibiotics. However, even this is uncommon. Bacterial causes of stomach flu such as salmonella and e. Coli often go away on their own as well. 

Symptoms of stomach flu may include:

  • Vomiting
  • Abdominal pain
  • Diarrhea
  • Nausea
  • Fever
  • Chills
  • Weakness
  • Muscle pain
  • Weight loss
  • Decreased appetite

Depending on what is causing your illness, you could experience other symptoms as well.

Serious Symptoms

Excessive vomiting and diarrhea are what can lead to dehydration. Infants, children, older adults, and people with weakened immune systems are most at risk of being dehydrated from a stomach bug.

  • Infrequent urination, with no urination for 12 hours being a cause for concern
  • Very dark urine
  • Excessive thirst
  • Dry skin and mouth
  • Dizziness
  • Fatigue/extreme tiredness and lethargy

Both children and adults who are dehydrated may have "skin-tenting" where the skin does not flatten back out immediately if you pinch it.

In babies and small children specifically, also watch for:

  • Excessive irritability
  • No smiling or willingness to play
  • No wet diapers for more than three hours
  • No tears when crying
  • Sunken eyes or soft spot

When to See a Doctor

If you have any symptoms of dehydration, call your doctor. There are a few medications available by prescription that can help stop or decrease vomiting. People who are severely dehydrated may need IV fluids.

In addition, if you have any of these additional symptoms, seek medical attention right away.

  • Vomiting blood
  • Large amounts of blood or mucus in the stool
  • Confusion
  • Feeling lightheaded or fainting when standing
  • Severe abdominal pain
  • A child who is unusually sleepy or difficult to wake up
  • Accompanied by a fever greater than 101 degrees (call your doctor)
  • Dehydration
  • Persistent vomiting lasting two days or longer

A Word From Verywell

If you find yourself dealing with symptoms of the stomach flu, make sure you stay hydrated but don't try to drink too much too quickly. Overdoing it with fluids can cause more vomiting and create a vicious cycle. If you are just experiencing diarrhea, make sure you eat bland foods that won't cause too much stomach discomfort. 

There is a debate about whether the BRAT diet (bananas, rice, applesauce, and toast) is really helpful, but it certainly can't hurt, as long as you limit your intake of these foods to just while you are feeling ill. The concern is that people continue to eat this way after they have recovered, which results in a limited intake of proper nutrients that your body needs. 

Be sure to avoid foods that are spicy, fatty, or greasy while you have the stomach flu and don't drink alcohol or caffeine. Electrolyte drinks such as Gatorade or Pedialyte are the best way to rehydrate but regular water works too. 

Stomach viruses are highly contagious, so washing your hands and cleaning is essential. It is really hard to avoid passing it among family members living in the same house, but cleaning as much as possible will minimize the chances. 

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Article Sources

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