What to do
- 1Call 911 immediately — heatstroke is a life-threatening emergency.
- 2Move the person out of the heat into shade or air conditioning right away.
- 3Cool them aggressively, by whatever means you have — a cool tub or shower or a hose; sponging or misting with cool water while fanning; ice packs or cool wet towels on the neck, armpits, and groin; cover with cool damp sheets.
- 4If they are fully conscious and can drink, offer chilled water, an electrolyte sports drink, or another nonalcoholic, non-caffeinated drink.
- 5Begin CPR if they lose consciousness and show no signs of circulation.
- 6Keep cooling until EMS takes over — don't stop because they "seem a little better."
When to use it
- Hard activity in heat, or too long in a hot place — including a scout who pushed through heat exhaustion.
- The reason "buddy watches" and hydration/shade rules exist at summer camp and on hot hikes.
- Recognizing that a confused, stumbling, hot person in the heat is a medical emergency, not just "tired."
Common mistakes & safety
- Altered mental status in the heat = heatstroke until proven otherwise. Confusion, weird behavior, slurred speech, or collapse is the line — cross it and you call 911 and cool hard.
- Cool first and fast — cooling is the treatment. Every minute at a dangerous temperature damages the brain and organs; aggressive cooling can't wait for the ambulance.
- Don't force fluids on someone who isn't fully alert. They can't protect their airway — cooling, not drinking, is the priority.
- Sweating does not rule it out. Exertional heatstroke often still has sweating — judge by mental status and temperature, not skin dryness.
- Keep cooling even if they perk up. They can crash again — this is a hospital problem, not a "walk it off" one.
- Prevent it: hydrate, rest in shade, pace hard activity, acclimatize gradually, and never leave anyone in a hot vehicle.
Going deeper
- The dividing line. Heat exhaustion — mostly there mentally, cool moist skin, responds to rest and fluids. Heatstroke — not right in the head, very high temperature, a 911 emergency needing aggressive cooling. Mental status is the line.
- Exertional vs. classic. Young, active people tend toward exertional heatstroke (often still sweating) from hard effort; the very old or young get classic heatstroke (often hot, dry skin) from environmental heat. Both are emergencies.
- Cold-water immersion is the gold-standard field cooling for exertional heatstroke where it's available and safe — the fastest way to drop core temperature.
Official source
Heatstroke: first aid — Mayo Clinic →This is general first-aid information, not a substitute for hands-on training. Suspected heatstroke is a 911 emergency — cool aggressively while you wait.