“The elderly and the sick are most susceptible to heat-related illnesses, but anyone who’s out and about when it’s hot is at risk, especially those who exercise in the heat” said Colin Grissom, MD, a critical care physician and wilderness medicine expert at Intermountain Medical Center.

Here are three important things Dr. Grissom says you can do to avoid heat-related illness this summer:

1. Avoid exerting yourself during the hottest part of the day. If you want to do some yard work, go running, or take a hike, do it in the morning or evening when temperatures are lower.
2. Stay hydrated. Drink plenty of water. If you’re thirsty at all, it’s time to start drinking. If you’ll be out working or exercising for more than two hours, you’ll also need some electrolytes, either from a liquid that contains electrolytes — such as Gatorade — or from salty snacks.
   A word of caution: Dr. Grissom warns that drinking too much water during prolonged periods of exercise in the heat can lead to a dangerous and sometimes fatal condition called hyponatremia. Endurance athletes who are exercising for over several hours in the heat are at the greatest risk. “Just don’t force yourself to drink a bunch of water when you’re not thirsty, and make sure you’re getting plenty of electrolytes,” Dr. Grissom said. “For periods of exercise lasting a couple of hours or less, water is an adequate fluid for hydration.”
3. Protect yourself from the sun. Wear sunscreen, lip balm, a hat, and loose-fitting clothing anytime you’ll be out in the sun. “As you get higher up in the mountains you’ll be more vulnerable to the sun,” warns Dr. Grissom. “I recommend you use at least SPF 30 sunscreen applied frequently if you’ll be out in the wilderness.”

What should you do if you have heat stroke or heat exhaustion?
Signs of heat exhaustion include intense thirst, weakness, discomfort, and dizziness. If you experience any of these symptoms, rest in the shade or a cool place and drink cool liquids. It can also help to sit by a fan or immerse yourself in cool water.

Heat exhaustion can lead to heat stroke, which is potentially fatal. Symptoms include confusion and altered mental status, seizures, and loss of consciousness.

“If a person has heat stroke, we need to bring their temperature down right away or they could die,” Dr. Grissom said. “Someone who has symptoms of heat exhaustion and who develops an altered mental status may be succumbing to heat stroke and need to get out of the heat and seek medical attention immediately. Applying ice packs to the groin and armpits can help during transport to an emergency department.”