Monday marks National Heat Stroke Prevention Day and with extreme heat forecast for later this week, doctors are worried about people overheating.

Heat stroke can happen by simply being overheated in hot weather or from physical activity in high temperatures. It can be very dangerous, damaging your brain, kidney's and muscle. In serious cases, it can lead to death. Symptoms include a throbbing headache, dizziness and lack of sweating despite the heat.

“When you stop sweating that's really bad especially if you are bright red and you notice that your temperature is skyrocketing and you more or less exhausted any sort of sweat supply that you had left,” says Doctor Markus Boos of Seattle Children’s.

Boos says the best defense against heat stroke is to drink lots of water.

“If you are feeling thirsty you are already starting to get behind the eight ball so you really want to make sure that you are staying hydrated all day long when it's going to be a warm hot day,” explains Dr. Boos.

Why take chances? If it's really hot medical professionals suggest you skip the park and plan indoor activities, like taking the family to the movies or even the aquarium.

“Making sure they are not outside too much keeping them in the shade as much as possible making sure they're staying hydrated those are the keys,” says Dr. Boos.

There is a nationwide campaign being promoted on social media called ‘look before you lock.’ They are using the hashtags #heatstrokekills and #checkforbaby hoping to raise awareness not to leave children or pets in cars.