The stages of stomach flu (viral gastroenteritis) generally follow exposure, incubation, an acute phase with peak symptoms (vomiting, diarrhea, cramps), and a recovery phase, though you remain contagious even as you feel better. Key stages include the incubation period (1-3 days before symptoms), the acute phase (sudden, intense symptoms for 1-3 days), and recovery, where symptoms fade but contagiousness can linger.
During the initial 24 to 72 hours, you'll likely experience the most intense symptoms, including vomiting, diarrhea, and abdominal cramps. This is the acute phase of the illness. Gradual improvement. After this acute phase, you should notice a gradual improvement in your condition.
Some infections like traveler's diarrhea, gastroenteritis, and food poisoning can be associated with other body symptoms that might include enlarged lymph nodes (glands).
Duration: Generally, stomach flu lasts about 48 hours, but severe cases can last more than two weeks. Treatment: Most people do not need medical treatment for stomach flu. Focus on hydration and rest. To ease symptoms, your clinician may recommend anti-nausea or anti-diarrhea medications.
Self care
Stomach flu and stomach bug are informal terms for viral gastroenteritis, a sickness in which a viral infection causes inflammation in the stomach and intestines.
It's important to note that if diarrhea is caused by bacteria, your body needs to get rid of the bacteria first by letting diarrhea run its course. If they're taken too soon, anti-diarrheal medication can make symptoms worse and keep you from clearing the infection.
You'll notice your symptoms lessening when your immune system has won the battle against the virus. Eventually, your symptoms will stop, and you'll feel better. But you may continue to shed the virus in your poop (stool) for a few days, which means you're still contagious.
The Worst Foods for Your Gastrointestinal System
Gastroenteritis is often mistaken for stomach flu although it is actually an inflammation of the lining of the intestines caused by a virus, bacteria or parasites. Symptoms of gastroenteritis include diarrhea, abdominal pain, vomiting, headache, fever and chills. Most people recover with no treatment.
If you're an adult, call your health care provider if: You're not able to keep liquids down for 24 hours. You've been vomiting or having diarrhea for more than two days. You're vomiting blood.
Early-stage lymphomas may not cause symptoms. When they happen, symptoms of lymphoma may include: Swollen lymph nodes, which might feel like a lump under the skin. They happen most often in the neck, armpit and groin.
Does drinking a lot of water help swollen lymph nodes? Drinking plenty of water can help avoid dehydration and promote good lymphatic system function.
Peak symptoms: The symptoms of norovirus often peak within 24 to 48 hours after they begin. This is when the vomiting and diarrhea can be most severe. Duration: In most cases, the symptoms gradually subside over the course of 1 to 3 days.
Make an appointment to see a doctor if you have:
With norovirus, you can be contagious before you feel ill. Symptoms usually appear within 1 to 2 days being exposed to the virus. Most people with norovirus feel better a day or two after their symptoms begin. But they're contagious for a few days after they recover.
Here, we break down the seven worst drinks for gut health and offer easy swaps that support better digestion and balance.
Some foods that can help manage IBS flare-ups include:
The hardest foods to digest are typically fried and fatty foods, processed foods, and some proteins like red meat, beans, and dairy (especially for lactose-intolerant individuals), along with high-fiber items like whole grains, cruciferous vegetables (broccoli, cabbage), and nuts/seeds, due to fat slowing digestion or fiber/complex carbs causing fermentation, gas, and bloating. Corn, spicy foods, onions, and caffeine can also be tough on the gut.
Six common signs of norovirus include sudden vomiting, watery diarrhea, stomach pain/cramps, nausea, headache, and muscle aches, often appearing 12-48 hours after exposure and lasting 1-3 days, leading to potential dehydration.
Food poisoning and gastro (gastroenteritis) both cause stomach upset, but the key differences are the cause (food poisoning from infected food/drink; gastro often viral/person-to-person) and timing, with food poisoning often hitting faster (hours) after exposure, while viral gastro usually starts 1-2 days later, though bacteria can cause both, making timing tricky, but food poisoning symptoms are often quicker and may be more intense but shorter.
What to drink when you have the stomach flu
Lifestyle and home remedies
Do not take loperamide if you:
To stop diarrhea, focus on bland, binding foods from the BRAT diet (bananas, rice, applesauce, toast) plus probiotics (yogurt), lean proteins (baked chicken), starchy foods (potatoes, crackers), and liquids (broth), while avoiding dairy, fats, fiber, caffeine, and spicy items to help firm stools and restore electrolytes.