Heat-related illness can range from mild conditions such as rash or cramps to very serious conditions such as heat stroke.
In Australia, every year, hot weather and heat waves cause illness, hospitalisations and sometimes death. It is important that everybody is aware of the signs and symptoms of heat-related illness in order to recognise and treat affected people promptly.
The best way to prevent heat-related illness is to drink plenty of water and to stay as cool as possible. Remember the 4 key messages to keep you and others healthy in the heat:
Heat-related illness includes dehydration, heat cramps, heat exhaustion, heat stroke and worsening of existing medical conditions. If you have a medical condition such as heart disease, diabetes, or kidney disease and if you take certain medications, heat can make your symptoms worse.
It is very important that a person’s body temperature stays in the range of 36.1 – 37.8°C. If body temperature rises above this, a person may develop heat-related illness. When the weather is very hot, the body has to work very hard and produce a lot of sweat to keep itself cool. It is more difficult for a person to sweat if it is humid, or if the person is already dehydrated.
Exposure to high temperatures can make existing illnesses seriously worse (for example trigger a heart attack), cause serious permanent injuries (damage to the brain or other vital organs) as a result of untreated heat stroke, and in extreme cases result in death.
Heat-related illness includes dehydration, heat cramps, heat exhaustion, heat stroke, and worsening of existing medical conditions. The most common health problem during periods of hot weather is worsening of existing medical conditions. The best way to prevent heat-related illness is to drink plenty of water and to stay as cool as possible.
Mild to moderate dehydration makes the heart work faster and leads to reduced fluid available for sweating.
Heat cramps usually affect people who sweat a lot during strenuous activity (e.g. sport or gardening). The sweating causes the body to lose salt and water. The low salt levels in the muscles may be the cause of heat cramps and they can be a symptom of heat exhaustion.
Heat exhaustion is the body’s response to an excessive loss of water and salt contained in sweat. If heat exhaustion is not treated, it can turn into heat stroke.
Heat stroke is a
life-threatening emergency and occurs when the body temperature rises above 40.5°C. Immediate first aid is very important, aim to lower body temperature as quickly as possible.
Everyone needs to take care in hot weather but some people are at greater risk of serious health effects from the heat than others, including:
Remember the 4 key messages to keep you and others healthy in the heat:
Beat the Heat for further information on:
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Multicultural Health Communication Service.