Skin is hot and dry because sweating has stopped. Treatable by very immediate cooling, removing all clothes, resting in a cool place, spraying with cool water and then fanning vigorously. Get the person to hospital immediately. This is a very serious condition. Every moments' delay increases the likelihood of death or permanent injury.
People are lethargic, have cramps and the symptoms of heat exhaustion.
Too much salt is harmful and a normal regular diet contains enough salt to replace what we lose in sweat. Workers involved in strenuous physical exertion. Workers who are dehydrated. Poor diet, vomiting, diarrhoea, alcohol consumption, and insufficient drinking can cause dehydration. The body cannot cool down if there is insufficient fluid for sweat production.