How to Tell the Difference – Cleveland Clinic

If your stomach is upset, you probably aren’t overly focused on the reasons for your bathroom emergency. All you want is to feel better.

But figuring out if you have food poisoning or the stomach flu can determine your best plan of action — and give you an indication of how long you’ll be miserable for.

Family medicine doctor Donald Ford, MD, MBA, chair of the Department of Family Medicine at the Cleveland Clinic, explains how to distinguish food poisoning symptoms from stomach flu and when to be concerned.

Causes of Stomach Flu and Food Poisoning

Stomach flu (also known as viral gastroenteritis) is very common. Like many viruses, it is passed on by groups of people who gather in close quarters.

“The classic environment in which we see the stomach flu walking around is a cruise ship,” says Dr. Ford. “People are in a closed structure and in very close contact with each other. Under these circumstances, the virus is transmitted very easily.”

In contrast, food poisoning comes from food. Bacteria can grow in food that has not been properly cooked or in food that has been stored for too long without refrigeration. dr Ford adds that some foods just aren’t right for you in general and would cause reactions similar to food poisoning.

The differences between food poisoning and the stomach flu

It can be very difficult to distinguish between food poisoning and the stomach flu as the two conditions have multiple symptoms.

Diarrhea is the main side effect of both. This can be watery and sometimes even bloody. “Bloody diarrhea often occurs when the diarrhea comes on very quickly,” says Dr. Ford. “It upsets the intestinal tract and causes a little bleeding.” Vomiting and nausea are also common symptoms, while some people may develop fever and chills with both.

However, the biggest differences between the two are when your symptoms start after exposure and how long your symptoms last.

onset of symptoms

The stomach flu usually has an incubation period of around 24 to 48 hours in your system and then it starts to cause symptoms. In contrast, food poisoning occurs quickly—usually about two to six hours after you eat spoiled food.

“Let’s say you sit down to a picnic and everyone eats the same thing,” says Dr. Ford. “It’s very possible that many people get the same symptoms. While with a gastrointestinal virus you may have been with someone who had similar symptoms in the past day or two. It takes a few days for it to kick in.”

Food poisoning can also be a little easier to spot since it occurs after a recent event. “Most people are comfortable with thinking about what they just ate and realize that maybe the egg salad was too long in coming,” says Dr. Ford. “They can then trace their symptoms back to that.”

How long the symptoms last

Food poisoning not only occurs faster than the stomach flu, it also progresses faster. dr Ford says viral gastroenteritis generally lasts two days, although sometimes it can last longer. In contrast, food poisoning “will hopefully clear your system sooner,” continues Dr. Ford continued. “It’s usually pretty short. I like to think of it as your body just trying to get rid of what it has ingested that is not good for it.”

Stomach Flu Symptoms

Stomach flu causes unpleasant symptoms such as nausea, diarrhea and vomiting. “With viral gastroenteritis, we tend to see a little more systemic effects like fever and chills,” says Dr. Ford. “But that’s not 100% true across the board.”

It is important to remember that the stomach flu is not the same as influenza. Although viruses cause both, they are very different. “Influenza is a respiratory disease and causes fever and chills, but also cough, shortness of breath and upper respiratory symptoms,” explains Dr. Ford. “The stomach flu can also cause fever and chills. But usually there is nausea and especially diarrhea.”

Food poisoning symptoms

Typical symptoms of food poisoning are vomiting and diarrhea. Sometimes these can be serious. Food poisoning can also occasionally cause a fever.

How to recover from food poisoning and the stomach flu

The treatment for food poisoning and the stomach flu is the same: get rest and drink plenty of water.

“The biggest risk of any of these diseases is dehydration,” says Dr. Ford. “When your body tries to get rid of what’s in there, it will throw out the good with the bad. It pushes out a lot of fluid along with the toxins that are making you sick. You have to be very aggressive when it comes to replacing them.”

Fever can also lead to dehydration. “When your body temperature goes up, it’s a response to the presence of something that’s troubling you,” notes Dr. Ford. “And that actually burns more liquid. Sometimes when you’re sweating from a fever, you know you’re losing fluids. But at other times you can’t even tell.”

When you are dehydrated, you also lose electrolytes from your body. Electrolytes are minerals found in your body, such as sodium, potassium, and magnesium, that help you absorb fluids better.

“Replacing electrolytes is also helpful in allowing your body to retain the water you’re trying to drink,” says Dr. Ford, who recommends pairing high-electrolyte drinks like Pedialyte® or Gatorade® with lots of H2O.

Both food poisoning and the stomach flu are so-called self-limiting diseases. In other words, you’ll get better on your own as conditions take their course.

“Very rarely do we need medication for any of these conditions,” says Dr. Ford. “Treatment consists of rest and fluid intake. Sometimes people want to take pills or something else that will help them get better quickly, which of course I understand. But antibiotics can actually make these symptoms worse. The drugs we use for influenza will not work.”

When to see a doctor for food poisoning or the stomach flu

However, there may be times when you need to see a doctor after food poisoning or a stomach flu. If you have a high fever, usually over 100 degrees Fahrenheit, you may want to get checked out.

“If you have other symptoms — like being overly sleepy, having trouble getting out of bed, or being unable to speak coherently — these are all possible signs of dehydration,” says Dr. Ford. “If you still don’t feel great after more than 48 hours, that’s a problem too. Sometimes you realize you’re getting better. However, if symptoms haven’t subsided — or if they appear to be getting worse at this point — it’s probably a good idea to at least contact the doctor’s office and discuss your symptoms.”

If you see a doctor, they’re likely to ask you questions about what you’ve eaten or who you’ve seen lately. “Doctors often go through a fairly detailed medical history of what has happened to you over the past few days to determine if you have food poisoning or the stomach flu,” says Dr. Ford. This in-depth interview is designed to help guide your treatment or identify what is going on.

Prevention is also key for both diseases. If a gastrointestinal virus is circulating, wash your hands. “That’s how it’s transmitted,” he continues. “People touch surfaces that the sick person touched. They accidentally touch their mouths and catch the virus.”

Food poisoning can also be prevented. If you’re at a large gathering or picnic where food has been sitting in the sun, food poisoning can occur even after just a few hours. “If you’re planning a picnic, keep that cooler cool and keep the food in the cooler for as long as possible,” advises Dr. Ford. “The more you’re allowed to sit outside in the sun in hot and humid weather, the more likely it is that bacteria will develop.”