So, advice on heat stroke and heat exhaustion below.
"The Mayo Clinic says that heatstroke is the most severe of the heat-related problems. Like heat exhaustion, it often results from exercise or heavy work in hot environments combined with inadequate fluid intake. Children, older adults, obese people, and people who do not sweat properly are at high risk of heatstroke. Other factors that increase the risk of heat stroke include dehydration, alcohol use, cardiovascular disease and certain medications. Heatstroke is life threatening because the body loses its ability to deal with heat stress...it can't sweat or control the body's temperature. Symptoms of heatstroke include rapid heartbeat, rapid and shallow breathing, elevated or lowered blood pressure, lack of sweating, irritability, confusion or unconsciousness, feeling dizzy or lightheaded, headache, nausea, and/or fainting."
