Gastro or Food Poisoning? Why the Label Matters Less Than the Red Flags

Over the Christmas break, I found myself on the other side of the fence — not as a paediatric nurse, but as the patient. I was struck down with what I’m still not entirely sure was gastroenteritis or food poisoning. What I do know is that for five solid days, my output was far greater than my input, and despite doing “all the right things,” I ended up spending 24 hours in hospital for rehydration and IV medications.

I’m still waiting on my stool sample results to confirm the exact diagnosis — and that in itself highlights an important point. Sometimes, even with medical investigations, the distinction isn’t immediately clear. And importantly, this can happen to anyone. When these illnesses enter a household, they rarely stop at one person — often moving swiftly through the family, one by one.

That experience felt like the perfect opportunity to talk about the differences between gastroenteritis and food poisoning, and more importantly, when we should worry, escalate care, and advocate for our little people at home when symptoms start to tip from “manageable” to “not okay.”

Gastroenteritis vs Food Poisoning — What’s the Difference?

When your child suddenly starts vomiting or has diarrhoea, it’s natural to ask:“Is this gastro or food poisoning?”

The tricky part? The symptoms are very similar.

Vomiting, diarrhoea, tummy cramps, nausea, fever, fatigue — both conditions can look almost identical, especially in the early stages. And for parents at home, it’s often not possible to tell the difference straight away.

So… does it really matter which one it is?

In most cases — not initially.

Why? Because the early management is the same, regardless of the label:

• Supporting hydration

• Monitoring symptoms

• Watching for signs of deterioration

What matters far more than the name is how your child is coping.

What Is Gastroenteritis?

Gastroenteritis — commonly called gastro — is inflammation of the stomach and intestines. It’s most often caused by a virus, but bacteria and parasites can also be responsible.

Common features include:

• Vomiting

• Watery stool known as diarrhoea

• Tummy pain or cramping

• Fever

• Lethargy or irritability

Symptoms often start within 1–2 days after exposure and usually settle within a few days, though some children take longer to bounce back.

Gastro spreads very easily, especially in households, daycares and schools — which is why once one person gets it, it often sweeps through the entire family.

What Is Food Poisoning?

Food poisoning is a type of gastroenteritis caused by eating food contaminated with bacteria, viruses, parasites, or toxins.

The symptoms are very similar:

• Vomiting

• Water stool known as Diarrhoea

• Abdominal pain and cramping

• Nausea

• Sometimes fever

One of the key differences is that food poisoning symptoms often begin much faster — sometimes within hours of eating the contaminated food.

But here’s the catch: From a parent’s perspective at home, you usually can’t tell the difference based on symptom

s alone.

What Parents Should Focus On Instead

Rather than trying to diagnose which illness it is, shift your focus to what is your child actually telling you with their symptoms.

Ask yourself:

• How is this affecting my child?

• Are they coping?

• Are things improving… or worsening?

• 
  

Key Things to Watch Closely

Hydration This is the big one. Vomiting and diarrhoea cause rapid fluid loss, especially in babies and young children. Small, frequent sips of fluid or oral rehydration solution are key.

Energy & Responsiveness Is your child alert and interacting — or unusually sleepy, floppy, or difficult to wake?

Urine Output Fewer wet nappies, dark urine, or not weeing for long periods can be signs of dehydration.

Ability to Keep Fluids Down If every sip leads to vomiting, that’s a red flag.

What’s Coming Out Green vomit, blood, or mucus in vomit or diarrhoea needs medical review.

Remember - We always want our INPUT greater than our OUTPUT

When to Worry and Escalate Care

Seek medical advice or urgent assessment if your child:

• Is under 6 months old

• Cannot keep fluids down (Output is greater than Input)

• Shows signs of dehydration - cracked lips, less than half wet nappies, dry mucous membranes

• Is unusually lethargic, floppy, difficult to rouse or not acting like themselves

• Has severe tummy pain

• Has green vomit or blood in vomit or stool

  
  

These signs tell us how sick a child is — and that matters far more than whether we call it gastro or food poisoning when you're deciding what's the best way to manage this at home or seek further assistance.

The Sick Sense Take-Home Message

You don’t need to know the exact diagnosis straight away to be a good parent or advocate.

What you do need is:

• Awareness of severity - Know the signs, utilise your Sick Sense and tool kit your Sick Sense workshop/online courses have taught you

• Confidence to monitor symptoms and know what to look for.

• Trust in your instincts - Those are your Sick Sense. Remember you are the expert of your child!

• Willingness to escalate when something doesn’t feel right

  
  

Sometimes, even adults end up needing IV fluids — and kids can tip over much faster.

If your gut tells you something isn’t right, listen to it. That’s your Sick Sense.

Want to Know More?

Join our next face-to-face Baby & Child First Aid Workshop, or jump into The Sick Sense Bite-Sized Online Course.

Practical, parent-friendly education with 24/7 access — straight in your back pocket when you need it most.

DISCLAIMER - The information shared in this blog is intended for general education and awareness only and does not replace individual medical advice. Every child and situation is different. If you are concerned about your child’s symptoms, notice signs of deterioration, or feel something isn’t right, seek advice from your GP, local health service, or emergency services. Always trust your instincts — parents know their children best.