Diseases

Exhaustion and collapse due to overheating of the body and loss of fluids following unaccustomed or prolonged exposure to excessive heat.

Persons most commonly affected: All age groups and both sexes but more common in elderly persons.
Organ or part of body involved: All body systems.
Symptoms and indications: Blood pressure and pulse rate fall and this is accompanied by fatigue, light-headedness and possibly, muscular cramps. The person feels thirsty, has an headache, feels dizziness and possibly has nausea or vomiting, urinates less frequently and is usually pale, but the skin may be moist and the temperature near to normal.
Causes and risk factors: Unaccustomed or prolonged exposure to excessive heat. More common in hot climates and results from excessive sweating, leading to loss of fluids and salts and disturbances of the electrolyte balance in body fluids. The risk increases with gastrointestinal disorders where there has been vomiting and diarrhoea, and if conditions are humid as well as hot.
Prevention: Gradual acclimatisation to the heat, especially if hard physical work is to be carried out, and drinking lots of fluids.