Flu & Diarrhea: How Are They Connected?

Viral gastroenteritis, or the “stomach flu” is different from the “real flu” known as influenza. Influenza impacts mainly the respiratory system (throat, nose, and lungs), while the stomach flu leads to irritation and inflammation of the stomach and intestines. This assault on the body typically presents itself with vomiting and non-stop trips to the bathroom.

Stomach Flu Symptoms

Gastroenteritis can affect individuals of all ages, race, backgrounds, and occurs world wide. Children, the elderly, those with weakened immune systems, and those in close quarters are most at risk. Common flu symptoms include but are not limited to the following (1):

  • Abdominal cramps and pain
  • Watery, usually non bloody diarrhea. If there is blood it may indicate a different and more severe infection.
  • Nausea, vomiting or both
  • Low grade fever
  • Chills, muscle aches and/or headache
  • Fatigue
  • Loss of appetite

Angry Tummy

Most Common Stomach Flu Causes

Other viruses, such as adenovirus, bacteria, parasites as well as food-borne illnesses may cause similar symptoms. However, here are a few of the most common causes.


This virus is highly contagious and known to doctors for being a “family affair” and many people associate it with cruise ships. The reason behind this, is that if one person in the family gets it, it's probable that everyone in the family will contract it. This is also why it spreads so rapidly in close quarters such as on cruise ships. Symptoms range from mild to severe and symptoms appear 1-3 days after infection. Often times lasting 1-2 days but up to 10 days. A person is contagious from onset of symptoms until 3 days to 2 weeks after recovery. The good news is most people feel better after 24-48 hours.


This virus is more common in children but can certainly still infect adults. Onset of symptoms is typically 1-3 days from exposure, however an individual may contagious prior to symptom onset and up to 2 weeks after recovery. (2)


This is a main cause of gastroenteritis and acute diarrhea in infants and children. Symptoms typically manifest within 2-3 days after infection and last for around 2-3 days. (3)

Kid with upset stomach, stomach flu and symptoms

How is the Stomach Flu Spread?

  • Contact with infected stool or vomit
  • Sharing food, beverages, or utensils
  • Touching contaminated objects (fomites) and then touching face, mouth, nose, eyes.
  • Treating someone with the stomach flu. A great example would be parents caring for their children.

Conventional Treatments

It is important to note that the flu shot does not protect against the stomach flu. Gastroenteritis (stomach flu) is NOT caused by  the influenza virus. Flu shots are designed to prevent the influenza virus. In addition, antibiotics do not work against viruses and therefore will not cure a stomach flu.

Stomach flu and pathogens

Prescription and over the counter medications for nausea, vomiting, fever and diarrhea are often used. However, using anti-diarrheal medications can make it more difficult to eliminate the virus. A few examples include acetaminophen, sports drinks, ginger ale, and broth.

How to Get Rid of the Stomach Flu: Home Remedies

It is possible to just wait 24-48 hours for the symptoms to pass. However, if you want to feel better faster and want some relief, check out these at home remedies that can help aid in the recovery process.


The stomach flu often leads to vomiting and diarrhea which can cause a lot of fluid loss. This includes the loss of electrolytes. This is why it is so important to stay hydrated. Drink lots of liquids such as water, cucumber water, coconut water, broth, non- caffeinated electrolyte beverages and herbal teas. Herbal teas such as ginger and peppermint are not only hydrating but are good at calming an uneasy stomach. Ginger is beneficial for nausea and vomiting. Suck on ice cubes if you need too. Just make sure to stay hydrated!

Flu and Diarrhea

Severe dehydration could lead to a trip to the hospital and IV fluids. So drink up! Make sure to see your doctor if you have not been able to keep any fluids down for 24hrs, are showing signs of dehydration, have a fever above 102F, or if vomit or stool contain blood.

Stomach Flu: What to Eat?

Loss of appetite is very common. It is recommended to avoid solid foods for a few hours if you have been vomiting or are experiencing nausea.  When you are ready to eat again, try the BRAT diet. BRAT stands for bananas, rice, applesauce, and toast. These simple foods are great for short term recovery but not intended to be used long term.

What Not to Eat

Avoid sugar, alcohol, caffeinated beverages, tomato products, dairy, fatty, greasy, and spicy foods. It is important to avoid caffeine in particular because it causes contractions in the GI tract, making symptoms more severe. In addition, alcohol is a diuretic as well upsetting to the stomach. Dairy and tomatoes can also be rough on an irritated digestive system. 


Probiotics are great for both viruses and bad bacteria in the gut. Foods such as keifer, yogurt, and kimchi are good sources. There are also probiotic dietary supplements but make sure to get a high quality one from a reputable source.  It is thought that probiotics reach the bowels and help combat the harmful pathogens that are causing the diarrhea. When you have the flu and diarrhea, probiotics have been found to help make diarrhea go away one day faster. (4)

Take it Easy and Rest!

If you have the stomach flu, you are probably exhausted with all the vomiting, diarrhea, and fatigue. Be easy on yourself and allow yourself to just rest. Your body is fighting a war, and giving it time to defeat the virus as well as rebuild is essential to a faster recovery. It’s okay not to be Superman all the time. Take care of yourself and work to make yourself as comfortable as possible. If you are lucky, the misery won’t last longer than a day or two.

Dr Danielle




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