Heat Stroke Signs & First Aid: What To Do in a Heatwave

What does it mean?

Every summer, Pakistan's heatwaves turn deadly — in cities like Karachi, Lahore, Jacobabad and Sibi, temperatures climb past what the human body can handle. When the body's cooling system fails, core temperature shoots up and organs begin to shut down. That is heat stroke — a medical emergency that can kill within hours if not treated. Before it comes heat exhaustion, a warning stage that is still reversible. Most heat deaths are preventable: they happen because people do not recognize the signs, delay cooling, or leave vulnerable family members unprotected. Knowing the difference between the two conditions — and what to do in the first minutes — saves lives.

Common causes

• 1Heat stroke signs (CDC):
  high body temperature (103°F / 39.4°C or higher), hot/red/dry or damp skin, a fast, strong pulse, headache, dizziness, nausea, confusion, and losing consciousness. The CDC calls heat stroke a medical emergency — call for help right away.
• 2Heat exhaustion signs (CDC):
  heavy sweating; cold, pale, clammy skin; fast, weak pulse; nausea or vomiting; muscle cramps; tiredness or weakness; dizziness; headache; fainting. The key difference: in heat exhaustion the person is still sweating and thinking clearly; in heat stroke, sweating may stop and thinking breaks down.
• 3Heat exhaustion can become heat stroke quickly
  if not treated — so never "wait and see" with worsening symptoms.
• 4First aid for heat stroke:
  move the person to a cooler place, and help lower their temperature with cool cloths or a cool bath. Do not give the person anything to drink — a confused or unconscious person can choke.
• 5First aid for heat exhaustion:
  move to a cool place, loosen clothes, put cool wet cloths on the body or take a cool bath, and sip water. Get medical help right away if the person is throwing up, symptoms get worse, or symptoms last longer than 1 hour.
• 6Who is most at risk:
  infants and young children, older adults, and people with chronic medical conditions, plus outdoor labourers, athletes, and anyone without access to shade, water or cooling. In Pakistan, think of the elderly at home alone, children playing outside at midday, and mazdoors working under the sun.
• 7Never leave children (or anyone) in a parked vehicle
  temperatures inside rise to lethal levels within minutes, even with windows slightly open.

When to worry

Prevention & practical tips

• ✓If you suspect heat stroke: call 1122 immediately. This is an emergency — say clearly that you think it is heat stroke. Then start cooling while waiting.
• ✓Cool the person rapidly, by any means available: move them to shade or indoors; pour or sponge cool (not ice-cold) water over the skin; apply wet cloths; fan them vigorously; place ice or cold packs on the neck, armpits and groin if available. Continue until help arrives.
• ✓Do NOT give fluids to someone with suspected heat stroke — especially if they are confused, vomiting or unconscious. (This is different from heat exhaustion, where sipping water helps.)
• ✓For heat exhaustion: get to shade, loosen clothing, lie down with legs slightly raised, apply cool wet cloths, and sip cool water slowly. Rest — do not return to work or play the same day.
• ✓Prevent it in the first place: Drink water regularly through the day — do not wait until you feel thirsty. Avoid very sugary drinks, excess tea/coffee and alcohol in extreme heat. Time outdoor work and exercise for early morning or evening; rest in shade frequently during peak heat (roughly 11am–4pm). Wear light, loose, light-coloured clothing and cover your head. Eat light; heavy hot meals add to the body's heat load. Check on the elderly, the sick, and neighbours living alone at least once a day during a heatwave. Keep homes ventilated; if you have a cooler, fan or AC, use it during the hottest hours. Wet curtains (khas ki tatti) and cross-ventilation help where there is no AC. Want a number for your own needs? Check how much water you need daily.
• ✓At the first sign of heat exhaustion in yourself or others, stop and cool down — it is far easier to reverse than heat stroke.

FAQs

References

• high body temperature (103°F / 39.4°C or higher): https://www.cdc.gov/natural-disasters/media/pdfs/2026/09/Heat_Related_Illness-NEWLOGO.pdf
• stacks.cdc.gov: https://stacks.cdc.gov/view/cdc/138804/cdc_138804_DS1.pdf