Get the person out of the heat immediately, lay them flat on a cool surface, and elevate their legs above heart level so gravity can return blood to the brain. Most people regain consciousness within 30 to 60 seconds of being in that position.
You're sitting in a sauna, maybe 10 minutes in, and the person next to you slumps over. No warning. No "I don't feel so good." Just gone.
This is one of those moments where knowing what to do matters more than anything else. Sauna fainting isn't rare — it happens when blood vessels dilate from heat, blood pools in the legs, and the brain doesn't get enough oxygen for a few seconds. Most people recover quickly once they're horizontal. But how you handle those first 60 seconds determines whether recovery is uneventful or becomes a medical emergency.
Here's exactly what to do, in order.
Get Them Out of the Heat Immediately
Don't try to revive them while they're sitting up. Don't fan them and wait. The priority is getting their body out of the environment that caused the problem.
If you can lift them, carry them out. If they're large or you can't safely move them alone, open the sauna door wide to let heat escape and lower them to the floor. Every second in that hot air keeps their blood vessels dilated and their brain struggling.
What not to do: Pour cold water on their face or chest. The sudden shock can cause a reflex gasp that pulls hot air into their lungs, and it does nothing to address the underlying cause — low blood flow to the brain.
Lay Them Flat and Elevate the Legs
Once they're on a cool surface, lay them on their back. Elevate their legs above heart level — prop them on a bench, a folded towel, or your own thighs if nothing else is available.
This isn't a nice-to-have. It's the single most effective physical intervention for fainting. Gravity pulls blood into the legs when you're upright. Lifting the legs above the heart uses gravity to help return that blood to the brain. Most people regain consciousness within 30 to 60 seconds of being in this position.
If they don't come around within two minutes, that's not simple fainting anymore. That's a medical event.
Check Their Airway and Breathing
Once they're flat, tilt their head back slightly and check if they're breathing. Look for chest rise. Listen for breath sounds. Feel for air on your cheek.
If they're breathing normally and their pulse is present, you wait. Keep them lying down. Don't sit them up just because they open their eyes — sitting up too fast can cause them to faint again.
If they're not breathing or you can't find a pulse, start CPR immediately. The American Heart Association recommends hands-only CPR for adults: push hard and fast in the center of the chest at 100 to 120 compressions per minute. Don't stop until emergency services arrive.
Call Emergency Services If Needed
You need to call for help if any of these are true:
- They don't regain consciousness within two minutes
- They're not breathing or have no pulse
- They hit their head when they fell
- They have chest pain, confusion, or difficulty speaking after waking up
- They have a known heart condition or are over 60
- They had a seizure during or after the episode
When you call, say exactly this: "Someone fainted in a sauna. They are not responding. We are at [location]." Don't over-explain. Stay on the line and follow instructions.
What Not to Do (Seriously)
A few common responses that make things worse:
Don't give them water. Not yet. If they're still unconscious or barely conscious, they can choke. Wait until they're fully alert and sitting up on their own.
Don't let them "walk it off." Walking upright after a faint is how people faint again. The body needs time to normalize blood pressure. Keep them lying down for at least 10 to 15 minutes after they regain consciousness.
Don't pour cold water on them. Already mentioned, but worth repeating. The shock can cause cardiac arrhythmia in someone who's already stressed. Cool air is fine. Cold water is not.
Don't put them back in the sauna. Some people wake up embarrassed and want to "finish their session." Don't let them. Their body just told you it couldn't handle the heat. Listen.
Why This Happens (The Short Version)
The mechanism is straightforward. Heat causes blood vessels to widen (vasodilation). Blood pools in the legs and gut. Less blood returns to the heart. Heart rate increases to compensate, but if you stand up or the heat is intense enough, blood pressure drops and the brain doesn't get enough oxygen. You faint.
This is more likely if someone is dehydrated, hasn't eaten, has been drinking alcohol, or has a pre-existing condition that affects blood pressure regulation. It's also more common in the first few minutes of a session before the body has adapted, or right at the end when someone stands up too quickly to leave.
After the Incident
Once the person is fully alert, sitting up comfortably, and has been stable for at least 15 minutes, they should still see a doctor. Not necessarily an emergency room visit, but a same-day or next-day checkup. Fainting in a sauna can be a one-off event caused by dehydration. It can also be the first sign of an underlying heart rhythm problem, low blood pressure, or another condition that needs attention.
If this happens to you personally, don't go back in the sauna until a doctor clears you. The research on sauna safety is clear: the vast majority of sauna sessions are safe, but the risk of sudden cardiac events increases in people with undiagnosed cardiovascular issues when exposed to extreme heat (Laukkanen et al., 2018, JAMA Internal Medicine).
One More Thing
If you're the one using the sauna regularly, the best prevention is simple: hydrate before you go in, don't go in on an empty stomach or after alcohol, and don't stand up quickly when you're done. Sit at the edge for a minute. Let your body adjust.
Most sauna fainting is preventable. But if it happens, you now know exactly what to do.
This information is for educational purposes. If you have a medical condition or are concerned about sauna safety, talk to your doctor before using a sauna.
Frequently asked questions
what should you do first if someone faints in a sauna
Your first move is to get them out of the hot environment as fast as possible. If you can't safely carry them out alone, open the sauna door wide to let the heat escape and lower them to the floor. Every extra second in the heat keeps their blood vessels dilated and their brain short on oxygen.
should you pour cold water on someone who fainted in a sauna
No, don't pour cold water on them. The sudden shock can trigger a reflex gasp that pulls hot air into the lungs, and it can also cause cardiac arrhythmia in someone whose body is already under stress. Cool air is fine, but cold water is not.
when should you call emergency services after a sauna fainting episode
Call for help if the person doesn't regain consciousness within two minutes, if they're not breathing or have no pulse, if they hit their head when they fell, or if they show chest pain, confusion, or difficulty speaking after waking up. You should also call if they have a known heart condition, are over 60, or had a seizure during or after the episode.
why do people faint in a sauna
Heat causes blood vessels to widen, so blood pools in the legs and gut rather than returning to the heart. The heart speeds up to compensate, but if the heat is intense enough or someone stands up too quickly, blood pressure drops and the brain doesn't get enough oxygen. Dehydration, not eating beforehand, and alcohol all make this more likely.