Heat stroke and heat exhaustion describe the same illness at different levels of severity. The Australian first aid guidance treats heat-induced illness as one condition on a spectrum, with heat stroke at the dangerous end of it. This guide covers the symptoms to look for, how to cool someone down safely, when to call an ambulance, and how long recovery takes.
Call 000 immediately if someone shows signs of a heat stroke. This guide is general information rather than medical advice.
Heat exhaustion vs heat stroke: are they different conditions?
Not according to current Australian first aid guidance. ANZCOR Guideline 9.3.4 treats the whole thing as heat induced illness, which presents with a spectrum of severity. Heat exhaustion and heat stroke describe points along that spectrum rather than two separate illnesses. Sunstroke is an older name for heat stroke that you might also hear or have heard throughout previous first aid training.
The important thing to note here is that you don’t have to diagnose which one you’re looking at before you act because the first aid is the same either way. You’ll want to get the person cool, get them out of heat, and watch how they respond. What changes with severity is how fast you call an ambulance.
Symptoms of heat exhaustion and heat stroke
ANZCOR lists eight signs of heat induced illness:
- Inability to continue the activity
- High body temperature
- Dizziness and faintness
- Nausea, vomiting or diarrhoea
- Pale skin and other signs of shock
- Dry skin
- Poor muscle control or weakness
- Decreasing levels of consciousness, confusion or seizures
Call 000 immediately if you see confusion, seizures, decreasing consciousness or collapse. Those signs mean the person is experiencing a more severe case of heat stroke, and Safe Work Australia says to call an ambulance straight away rather than waiting to see if cooling works. It also goes without saying, cool the person whilst waiting for the ambulance.
Someone who has stopped sweating despite the heat is also seriously unwell. ANZCOR notes this appears in only some serious cases, so a person who is still sweating heavily can be just as sick.
How to treat heat stroke and heat exhaustion
Start the same way for anyone. Lie the person down somewhere cool or shaded, then loosen and remove any excess clothing. Begin cooling straight away, though never let it delay calling an ambulance if the symptoms are severe.
How you cool them down depends on their age:
- For anyone over five: Immerse the whole body from the neck down in cool water for 15 minutes, using a bath if one is available. ANZCOR calls this the most effective method. If you don’t have a bath available, you can combine several approaches instead. Wet the person down with a shower or hose, apply ice packs to the groin, armpits, facial cheeks, palms and soles, moisten their skin repeatedly with a wet cloth or spray bottle, and fan them continuously. Do not immerse a person who is hot into cold water or ice bath as this can cause severe cardiac issues, including cardiac arrest.
- For children five and under: Use tepid water instead of cold. A lukewarm bath with frequent sponging works if you have one. Otherwise, moisten their skin repeatedly with a wet cloth or spray bottle and fan continuously. Be sure to remove all of their clothes to allow the skin to cool.
When to call an ambulance
Call 000 immediately if the person shows any sign of heat stroke. Safe Work Australia is clear that you shouldn’t wait to see whether cooling works before making the call. These signs mean you need to call an ambulance immediately:
- Confusion or disorientation
- Seizures
- Decreasing consciousness or collapse
- No longer sweating despite the heat
Call as well if a milder case isn’t improving or if you’re not sure how serious it is. ANZCOR tells first aiders it’s always best to send for an ambulance early rather than late. You will not have an issue from responding paramedics for calling them if they are not needed.
Keep cooling the person while you wait and keep checking if they’re still conscious and breathing normally. You can also give them water to drink if they’re fully conscious and able to swallow, but ensure the water consumed is not cold, and is consumed slowly.
How long does heat stroke last?
There’s no set answer, since recovery depends on how severe the illness was, how quickly cooling started, and whether any organ damage occurred. ANZCOR states plainly that the effect of cooling rate on recovery rate hasn’t been studied, so no Australian clinical source can give you an exact timeframe.
What is certain is that anyone who has had heat stroke needs proper medical assessment, even if they seem to bounce back quickly once they’re cool. Feeling better isn’t the same as being out of danger, as the effects of organ damage aren’t always evident right away.
Learn first aid with IPC
Reading about heat illness is useful, though practising the response is what makes you act quickly when it matters. HLTAID011 Provide First Aid covers environmental emergencies along with CPR, bleeding control and the other situations first aiders face. If you work outdoors or somewhere remote, HLTAID013 Provide First Aid in Remote or Isolated Sites covers how to respond when help is a long way off.
FAQs
Is sunstroke the same as heat stroke?
Yes. Sunstroke is an older, informal name for heat stroke. The symptoms and the first aid response are identical, so treat it the same way.
What’s the difference between heat exhaustion and heat stroke?
Severity. Australian first aid guidance treats them as one condition on a spectrum rather than two separate illnesses. Heat stroke is the emergency end, marked by confusion, seizures or loss of consciousness.
What’s the first sign that heat exhaustion is becoming a heat stroke?
A change in mental state. Confusion, disorientation or dizziness that won’t clear are the signs to watch for, along with someone who stops sweating despite the heat. Call 000 if you see any of those signs.
Can you treat heat stroke at home?
No. You can manage it by cooling immediately while you wait for the ambulance to arrive, though anyone showing signs of heat stroke needs medical assessment. Cooling someone down successfully doesn’t remove the need for a medical evaluation, as internal organ damage might not show right away.
This guide describes what ANZCOR and Safe Work Australia publish rather than replacing training or medical advice. Call 000 for any sign of heat stroke.
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