Diarrhea vs. Stomach Flu

Diarrhea is a common symptom of the stomach flu, but it also occurs with many other conditions. Understanding the stomach flu and the different ways diarrhea can manifest will help you know if you have a viral illness that will pass in a few days, or if something more serious. Here’s a look at the differences between the stomach flu and diarrhea.

What is Diarrhea?

Diarrhea is generally a symptom of something rather than an actual illness. It generally takes 2 days to 2 weeks to clear up when it is the result of an infection (viral, bacterial, or otherwise). Food poisoning and some medications can also cause a serious case of diarrhea. Certain surgeries and tumors can lead to diarrhea, as can some cancer treatments. Diarrhea is considered chronic when it lasts for more than four weeks. Chronic diarrhea can be the result of many things, among them:

  • An allergy or intolerance to food (lactose intolerance, celiac disease)
  • Overindulgence in certain substances (alcohol, caffeine, artificial sweeteners, and some sugars)
  • Inflammatory bowel diseases
  • Irritable bowel syndrome
  • Ischemic bowel disease
  • Hormonal disorders

What is a Stomach Flu?

A stomach flu, or viral gastroenteritis, is the body’s response to an invasion of pathogens. Symptoms that may accompany the flu include loose or watery stool (diarrhea), nausea, vomiting, abdominal pain, fever, headaches, and a general feeling of malaise or fatigue.

The stomach flu is caused by contact with someone who is infected and currently contagious. This means sharing food, utensils, or even towels, as well as by second-hand contact. Ingesting contaminated food or water can also cause the flu. Among the more common versions of the flu are norovirus and rotavirus, although different forms of the flu can appear from year to year (such as the bird flu or swine flu).

In most cases treatment for the flu is simply time. Because it is the result of a virus, few medications can kill the pathogen to help you recover quicker. However, new medication designed specifically to fight the flu can shorten the duration, as can some antivirals in certain situations. Chronic diseases may require long term medication and dietary changes to manage it. Antidiarrheal medications often help acute infections. If you think something in your diet is causing diarrhea, try not eating it for a few weeks to see if there is a change. If your medication causes diarrhea, talk to your doctor about an alternative.

What’s the Difference?

The biggest difference in the stomach flu and diarrhea is that the stomach flu is an illness while diarrhea is a symptom of an illness. One of the more important differences is the way diarrhea is contracted. While the stomach flu is always contagious, diarrhea is only contagious when it is the result of a contagious illness. Additionally, while the stomach flu is contracted through pathogens, diarrhea can be the result of something amiss in the body or gastrointestinal tract. The stomach flu should never be chronic, while diarrhea may be (although you should certainly go to the doctor if it lasts for more than even a few days).