Heat exhaustion and heat stroke are two conditions that can result from prolonged exposure to hot temperatures without adequate hydration. Heat exhaustion is a precursor to heat stroke, per the Mayo Clinic.
Heat exhaustion is characterized by significant sweating, loss of color, cramps, fatigue, fainting and dizziness. Heat stroke symptoms include a body temperature over 103 degrees Fahrenheit, dry skin, high heart rate, confusion and even unconsciousness.
According to the CDC, if you see someone affected with either heat exhaustion or heat stroke, call emergency services and get them out of the sun immediately and cool them with towels, water and fans.
Heat stroke can cause organ damage, brain damage and even death if not treated quickly. Heat exhaustion can lead to heat stroke if left untreated.
You can help prevent heat illness by staying hydrated, wearing sunscreen and avoiding strenuous activities outdoors on hot days. When you must go outside, make sure you have someone with you in case of an emergency.
Those most susceptible to heat-related conditions are seniors, young children, overweight individuals and those who already are ill or take certain drugs, especially diuretics.