Yes, an upset stomach is a recognized symptom of COVID-19. The CDC lists nausea, vomiting, and diarrhea on its official symptom list alongside the more familiar respiratory signs like cough and fever. Around 10% of adults with COVID experience digestive symptoms, though the exact number varies depending on the variant and the individual.
How Common Digestive Symptoms Are
A large meta-analysis pooling data from dozens of studies found that about 10% of adult COVID patients reported gastrointestinal symptoms overall. Breaking that down: diarrhea appeared in roughly 10.4% of cases, nausea or vomiting in 7.7%, and abdominal pain or discomfort in 6.9%. These numbers are lower than the rates for fever or cough, which is why digestive symptoms often get overlooked as a possible sign of infection.
One U.S. study of 207 COVID patients found a higher rate, with about 34.5% reporting at least one digestive symptom. The discrepancy likely reflects differences in how symptoms were tracked and how actively patients were asked about them. The takeaway: stomach trouble during COVID is not rare, but it’s also not the most common presentation.
Why COVID Affects Your Gut
The virus that causes COVID enters your cells through a specific receptor protein found on cell surfaces throughout your body. Your small intestine actually has the highest concentration of these receptors, even more than your lungs. That means the virus can directly infect the lining of your digestive tract, triggering inflammation, disrupting normal digestion, and causing symptoms like nausea, cramping, and diarrhea.
This gut infection can also shift the balance of bacteria in your intestines, reducing helpful species and allowing more harmful ones to flourish. That disruption in your gut microbiome helps explain why some people develop prolonged digestive issues even after the acute infection clears.
Symptom Patterns in Children
Children tend to show a different symptom profile than adults. Fever and cough are less dominant in kids, while digestive complaints are proportionally more prominent. About 9% of children with COVID experience diarrhea, 10% have vomiting, and 23% show reduced appetite or feeding difficulties. In up to 10% of pediatric cases, stomach symptoms are the only sign of infection, with no cough, fever, or congestion at all. This makes it easy to mistake a child’s COVID infection for a simple stomach bug.
How Variants Changed the Picture
The likelihood of digestive symptoms has shifted with different variants. The Delta variant produced diarrhea in about 14.6% of cases, while Omicron brought that number down to around 3.2%. Some research found no meaningful difference in abdominal pain or nausea between the two variants, but the overall trend with Omicron and its subvariants has been fewer digestive complaints compared to earlier strains.
Telling COVID Apart From a Stomach Bug
If your only symptom is an upset stomach, it can be difficult to know whether you’re dealing with COVID, food poisoning, or a standard stomach virus. A few patterns can help. Ordinary gastroenteritis (the classic “stomach flu”) typically peaks within one or two days and resolves quickly. COVID-related digestive symptoms tend to last longer, sometimes persisting for several days. You may also notice respiratory symptoms developing alongside or shortly after the stomach trouble, such as a sore throat, congestion, or a new cough. Loss of taste or smell, while less common with recent variants, remains a strong signal pointing toward COVID rather than a stomach virus.
The most reliable way to tell the difference is a COVID test. If your stomach symptoms last more than two days or you develop any respiratory signs, testing can clarify what you’re dealing with.
Digestive Symptoms and Severity
There is an association between digestive symptoms and more severe COVID illness. In one study, patients with any digestive symptom had roughly 4.8 times higher odds of needing hospitalization compared to those without gut involvement. Diarrhea specifically carried about a 7-fold increase in hospitalization risk, and nausea or vomiting about a 4-fold increase. Importantly, 90% of the digestive symptoms themselves were mild. Researchers aren’t sure whether the stomach trouble directly signals worse disease or whether it’s simply a marker of higher viral levels throughout the body.
This doesn’t mean that getting diarrhea with COVID should alarm you. Most people with digestive symptoms still recover at home without complications. But if your symptoms are worsening, especially if you develop shortness of breath or persistent fever alongside stomach problems, that combination warrants closer attention.
Managing an Upset Stomach at Home
The approach to COVID-related stomach symptoms is similar to managing any viral digestive illness. Staying hydrated is the priority, particularly if you’re dealing with diarrhea or vomiting. Water, broth, and oral rehydration solutions all help replace lost fluids and electrolytes. Small, bland meals are easier on an irritated stomach than large or rich ones.
Over-the-counter pain relievers like ibuprofen or acetaminophen can help with any accompanying fever, aches, or abdominal discomfort. Rest matters. Most people find their digestive symptoms improve within a few days to a week as the infection runs its course.
Long-Term Gut Effects After COVID
For some people, digestive problems don’t end when the acute infection does. Long COVID can include persistent gut symptoms that resemble irritable bowel syndrome: ongoing bloating, irregular bowel habits, abdominal pain, and food sensitivities that weren’t there before. Researchers believe this happens through a combination of lingering viral particles in the gut, sustained low-grade inflammation, and lasting changes to the microbiome.
These microbiome shifts can also affect how your body processes tryptophan, a building block for serotonin. Since serotonin plays a major role in gut motility and mood, this disruption may explain why some long COVID patients experience both digestive and neurological symptoms simultaneously. If your stomach issues persist for weeks after a COVID infection, that pattern is consistent with what clinicians now recognize as a post-infectious gut-brain disorder.