Hunter New England Local Health District reminds people to take necessary precautions in periods of hot weather and poor air quality to reduce their risk of illness, with heatwave conditions forecast this week.
The forecast heat will potentially break November records, while smoke from bushfires affecting the region will compound health risks.
Dr David Durrheim, a public health physician with Hunter New England Local Health District, urged people to avoid being outside during the hottest part of the day, to minimise physical activity and keep well hydrated.
"We're expecting temperatures over 40 for some areas of NSW. This is the first really hot period of summer, and I'd encourage everyone to take the risk of heat-related illness seriously," Dr Durrheim said.
"We know that heatwaves cause severe illness, hospital admission, and even deaths, and that people are more sensitive to heatwaves early in the season.
"The combination of heat and poor air quality adds to the risk. Hot weather puts a lot of strain on the body, causes dehydration and can make underlying health conditions worse. It also causes heat stress and heat stroke.
"People over 75, people with chronic medical conditions and people who live alone are particularly vulnerable.
"Simple precautions can reduce the risk of heat-related illness.
"It's best to stay indoors during the hottest part of the day, which is generally from about 11am to 4pm. Staying indoors also protects you from bushfire smoke. If you don't have air conditioning, using a fan can cool you down and keeping curtains shut helps to keep the heat out of your home. It's also important to minimise physical activity and to drink plenty of water.
"It's important to stay in contact with elderly neighbours, friends and relatives as they may be more vulnerable to the heat.
"Signs of heat-related illness include dizziness, tiredness, irritability, thirst, fainting, muscle pains or cramps, headache, changes in skin colour, rapid pulse, shallow breathing, vomiting, and confusion."
Dr Durrheim said it's important to get to a cool place quickly if symptoms occur.
People showing severe signs of heat-related illness should seek urgent medical attention, in an emergency situation call Triple Zero (000).
More information can be found at the NSW Health website: www.health.nsw.gov.au/environment/beattheheat.