Beating the Heat: Preventing Heat Exhaustion and Heat Stroke

How the body sheds heat, and the day it cannot

The human body is remarkably good at getting rid of heat until the day conditions defeat it. Its main tool is sweat, which cools not by being wet but by evaporating, each drop carrying heat away as it turns to vapour. A North Indian May, hot but dry, lets this system work if water keeps coming; the humid weeks before the monsoon are crueller, because sweat that cannot evaporate into saturated air cools nothing while still draining the body's water and salt. When heat gain outruns heat loss, the core temperature climbs, and everything from cramps to collapse follows that single arithmetic.

Heat exhaustion and heat stroke are not the same illness

Heat exhaustion is the body straining but still fighting: heavy sweating, weakness, giddiness on standing, headache, nausea, cramps and cool clammy skin, with the person tired but mentally clear. Heat stroke is the defence system failing: the core temperature soars, sweating may stop leaving the skin hot and dry, and, decisively, the brain malfunctions, confusion, strange behaviour, stumbling, fits or unconsciousness. That mental change is the dividing line every family should memorise. Exhaustion is treated with shade, fluids and cooling at home; stroke is a life-threatening emergency where organs are cooking, and it needs a hospital while cooling starts on the way.

Who the heat hunts first

Heat illness is not distributed fairly. Outdoor workers, construction labour, delivery riders, farmers, rickshaw pullers, absorb hours of direct load. Elders sense thirst late, sweat less and often take blood-pressure pills or diuretics that drain fluid; many heat deaths happen indoors in poorly ventilated rooms during heatwave nights. Small children heat up faster than adults, and a child left in a parked car is in danger within minutes, since cabin temperatures rocket even with windows cracked. Diabetics, heart patients and anyone with fever or diarrhoea in summer also stand closer to the edge than they feel.

Drinking to stay ahead, not to catch up

By the time thirst shouts, the body is already behind, so in serious heat drink by the clock: a glass of water every hour or so awake, more with outdoor work, aiming for urine that stays pale rather than dark and scanty, which is the honest household gauge. Long sweaty hours drain salt with the water, and plain water alone cannot replace it, which is where nimbu-pani with a pinch of salt, chhaach, coconut water or ORS earns its place. Alcohol and endless strong tea pull fluid out through the kidneys, and iced colas add sugar without salt; treat them as taste, not hydration.

Timing, clothing and the house itself

Arrange the day around the sun: outdoor errands, exercise and market trips before ten and after five, with the noon-to-four furnace ceded to shade wherever livelihood allows, and employers of outdoor labour owe their people shaded breaks and water in exactly those hours. Wear loose, light-coloured cotton that lets sweat evaporate, cover the head outdoors, and never leave a child or elder waiting in a parked vehicle. At home, shut curtains on the sunny side by mid-morning, open windows for the cooler night air, and remember a fan cools only if sweat can evaporate; on humid days a damp cloth on the skin in front of the fan works better.

First aid: cool first, and cool fast

For a person wilting in the heat, act on the spot: move them to shade or the coolest room, lay them down with legs slightly raised, strip away excess clothing, and cool the skin aggressively, water sponged or poured over the body, wet cloths at the neck, armpits and groin where big vessels run close to the skin, and a fan driving evaporation. If they are alert, give sips of ORS or salted nimbu-pani, never force fluid into a drowsy person. Improvement within thirty minutes is the expected course for heat exhaustion; anything less is a hospital matter.

When it is an emergency, not an episode

Go straight to hospital, cooling en route, for any confusion, abnormal behaviour, fits, fainting or unresponsiveness in the heat; skin that is burning hot and dry; a temperature reading around 40°C or above; repeated vomiting that defeats fluids; or no urine for many hours. Come to the clinic the same day for cramps and giddiness that return despite rest and fluids, for any heat symptoms in an elder, an infant, a pregnant woman or a heart or kidney patient, and after any spell of near-fainting at work in the sun. Heat stroke kills within hours, and the families who treat the first confused sentence as an alarm, not a joke about the garmi, are the ones who reach help in time.