Do I Have Food Poisoning or a Stomach Bug? Here’s How to Tell the Difference

You’ve been hit with nausea, stomach cramps, maybe even vomiting — but what’s actually causing it? Is it food poisoning or a stomach bug? The symptoms can be similar, but the causes, timing, and treatments can vary. Understanding the difference can help you recover faster — and know when to seek medical care.

Food Poisoning vs. Stomach Bug: What’s the Difference?

While both conditions affect your digestive system, they come from very different sources:

Food Poisoning

• Caused by contaminated food or drinks (bacteria, viruses, or toxins)
• Common sources include undercooked meat, spoiled dairy, or unwashed produce
• Usually hits within hours of eating

Stomach Bug (Viral Gastroenteritis)

• Caused by a virus (like norovirus or rotavirus)
• Spreads through contact with infected people or surfaces
• Often takes 1–2 days to develop after exposure

Common Symptoms of Food Poisoning

The onset of food poisoning is usually quick and intense, often starting within 6 hours of eating something bad. Symptoms may include:

• Nausea and vomiting
• Diarrhea (sometimes bloody)
• Stomach cramps
• Fever or chills
• Headache or muscle aches
• Weakness or fatigue

How Long Does Food Poisoning Last?

Most cases of food poisoning last 1 to 3 days, depending on the cause. Some people may recover in 24 hours, while others experience lingering fatigue or stomach sensitivity for a few more days.

Symptoms of a Stomach Bug

Stomach bugs, also known as viral gastroenteritis, can feel similar but usually come with more gradual onset and flu-like symptoms:

• Nausea and vomiting
• Watery (but not bloody) diarrhea
• Low-grade fever
• Body aches
• Mild dehydration

How Long Does a Stomach Bug Last?

Symptoms typically last 1 to 4 days, though some viral infections can stretch up to a week, especially in children or older adults.

Quick Comparison: Food Poisoning vs. Stomach Bug

When to See a Doctor

Most mild cases of food poisoning or stomach bugs clear up on their own. However, you should see a doctor if you experience:

• Symptoms lasting more than 3 days
• Blood in vomit or stool
• High fever (above 102°F)
• Signs of dehydration (dry mouth, dizziness, dark urine)
• Severe abdominal pain

BASS Medical Group’s Primary Care Providers can help determine the cause of your symptoms and recommend proper treatment, especially if you’re at risk of complications.

How to Feel Better Faster

No matter the cause, here are a few recovery tips:

• Stay hydrated with water, electrolyte drinks, or broth
• Avoid dairy, caffeine, and spicy foods while recovering
• Get plenty of rest
• Slowly reintroduce bland foods like toast, rice, bananas, or applesauce
• Wash your hands regularly to avoid spreading illness

Think You Have Food Poisoning or a Stomach Bug?

Whether it started after a meal or came out of nowhere, our providers can help you get relief. Contact BASS Medical Group to schedule an appointment with a primary care provider.

Frequently Asked Questions (FAQ)

Q: How can I tell if it’s food poisoning or a stomach bug?

Food poisoning often comes on quickly—usually within a few hours after eating contaminated food. A stomach bug (viral gastroenteritis) usually develops more gradually, with symptoms appearing 1–2 days after exposure to an infected person or surface.

Q: What is the main difference between a stomach bug and food poisoning?

The main difference is the source: food poisoning is caused by harmful bacteria or toxins in contaminated food or drinks, while a stomach bug is caused by a viral infection, often spread person-to-person.

Q: How long does food poisoning last?

Most cases last between 1 to 3 days. Some people recover in less than 24 hours, while others may experience fatigue or digestive upset for a few more days.

Q: Can you spread food poisoning to other people?

Most types of food poisoning are not contagious, but some bacterial infections (like Shigella) can spread. In contrast, stomach bugs—especially norovirus—are highly contagious.

Q: When should I see a doctor for food poisoning or a stomach bug?

Seek medical care if you experience symptoms for more than 3 days, have a high fever, notice blood in your stool or vomit, or show signs of dehydration.