How to Treat Heat Stroke: Step-by-Step First Aid

Heat stroke is one of the few medical situations where bystander action in the first 30 minutes genuinely changes the outcome. The body's core temperature is dangerously high and the brain is showing it — confusion, slurred speech, strange behavior, or unconsciousness. Damage is accumulating minute by minute. Aggressive cooling, started immediately, is the single most important treatment, and it can be done before EMS arrives.

This article is a practical step-by-step first aid sequence: what to do first, what to do next, what to keep doing, and what to avoid. It is written for the person on the scene who has to act, not for a textbook reader.

Recognize it first

Heat stroke first aid only works if you recognize what you are looking at. The two defining features are:

1. Body temperature above 104°F (40°C) — or strong signs of it: skin that feels burning hot to the back of your hand, sometimes dry, sometimes still sweating in exertional cases.
2. Brain involvement — confusion, disorientation, slurred speech, agitation, strange behavior, seizures, or loss of consciousness.

If both are present in a person who has been in heat or exerting in heat, treat it as heat stroke and act immediately. Do not wait to confirm with a thermometer if the picture is clear.

Step 1: Call for help

Have someone call emergency services right away. Do not wait until cooling is started — get help moving while you do the rest. If you are alone with the person, make the call, put the phone on speaker, and start cooling at the same time.

While on the call, give the dispatcher:

• That you suspect heat stroke
• The person's mental status (alert, confused, unconscious)
• Your location and a way for EMS to find you
• Whether they are breathing normally

Step 2: Get them out of the heat

Move the person to the coolest place quickly available. Order of preference:

1. An air-conditioned indoor space.
2. A shaded outdoor space with airflow.
3. Any shade at all.

Do not delay cooling to get to a "better" location if movement will take more than a minute or two. Starting cooling where you are beats spending five minutes carrying someone to a better spot.

Step 3: Strip down clothing

Remove as much clothing as is reasonable — outer layers, heavy fabrics, anything tight. The goal is exposed skin for evaporation and direct cooling. Keep underwear or basic modesty in place. Do not waste time on shoes and socks unless they are clearly contributing to heat retention.

Step 4: Start aggressive cooling — pick the best method available

The single most effective treatment is to drop core temperature as fast as possible. The best method depends on what you have:

• Cold water immersion (best when available). Put the person in a tub of cold water, a stock tank, a kiddie pool, or any container that can submerge the body up to the shoulders. Keep the head above water. This is the gold standard for exertional heat stroke in healthy adults and works dramatically faster than anything else.
• Continuous dousing with cold water. If immersion is not possible, soak the person continuously with cold water — hose, buckets, shower — while a fan or breeze blows over them. The combination of water and air is the key.
• Ice packs at major heat transfer sites. Place ice packs or bags of frozen vegetables at the neck (sides), armpits, and groin — places where large blood vessels run close to the skin. Combine with water dousing if possible.
• Wet sheets and fans. Wrap the person in wet sheets and run fans over them. Less effective than the above but still useful.
• Misting and fanning. Spray with cool water from a spray bottle and fan continuously.

Use whatever you have. Aggressive is the operative word — gentle cooling is not enough.

Step 5: Position safely

Lay the person on their side (recovery position) if they are unconscious, vomiting, or only partially responsive. This protects the airway if they vomit. If they are alert and able to sit, that is fine, but be ready for them to fade.

Step 6: Do not give fluids by mouth if they are not fully alert

This is one of the most common mistakes. If the person is confused, drowsy, or in any way not fully alert, do not pour water down their throat. The risk of aspiration is real and serious. If they are fully alert and able to sip on their own, small sips of cool water are reasonable, but fluid replacement is not the priority — cooling is.

EMS will handle IV fluids. Your job is to drop the temperature.

Step 7: Monitor and adjust

While cooling continues:

• Watch breathing. If breathing stops, start CPR if you are trained.
• Watch for seizures. Protect the head, do not put anything in the mouth, and let the seizure pass. Resume cooling immediately afterward.
• Watch temperature if you have a thermometer. A rectal thermometer is the most accurate; oral and forehead readings are less reliable in this situation but still useful as a trend.
• Stop aggressive cooling once core temperature drops to about 101°F to 102°F. Continuing past that risks overshooting into hypothermia. Switch to passive cooling — keep them in the shade, lightly damp, with airflow.

Step 8: Hand off to EMS clearly

When help arrives, give them a tight summary:

• What you saw and when
• Estimated time of onset and how long they have been at it
• What cooling methods you used and for how long
• Mental status now versus when you started
• Anything else relevant — medications, age, known medical conditions, alcohol or drug use

A clear handoff makes the next phase of care much faster.

What to avoid

A short list of things not to do, all of which come up:

• Do not delay cooling to wait for EMS. The first 30 minutes are yours, and they matter most.
• Do not give alcohol, caffeine, or salt tablets. None help in the acute phase.
• Do not pour ice water down the throat of someone not fully alert. Aspiration risk.
• Do not assume sweating means they are fine. Exertional heat stroke often still has sweating.
• Do not put them in a very hot bath afterward "to recover." Recovery is in a cool environment.
• Do not let them get back up and "walk it off." Even after they look better, they need medical evaluation.

A simple sequence to remember

If you remember nothing else, remember this order:

1. Recognize it (high temperature + altered mental status).
2. Call for help.
3. Get out of the heat.
4. Strip clothing.
5. Cool aggressively — immersion if possible, dousing and ice packs if not.
6. Position safely; do not force fluids if not fully alert.
7. Monitor and adjust; stop aggressive cooling around 101–102°F.
8. Hand off clearly to EMS.

Heat stroke and weather sensitivity

Heat stroke is the catastrophic end of a spectrum that the rest of summer plays out in milder forms — pressure-band headaches on hot afternoons, fatigue and brain fog when humidity stacks, migraines that arrive on the worst heat days of the season. For weather-sensitive readers, tracking heat index, humidity, and barometric pressure alongside symptoms is the cleanest way to see which days are stacking risk and which days are safer. The Pressure Pal app is built for that kind of multi-signal tracking, and the data tends to be most useful exactly when the weather is most demanding.

You probably will never have to use this sequence. If you do, knowing it cold and starting cooling immediately is the most useful thing anyone in the room can do.