Heatstroke is the most serious heat-related illness. Signs include a 40C/104F temperature, partial or total loss of consciousness, confusion and little or no sweating.
Heat stroke is a medical emergency. Call 911 or your local emergency number if this occurs.
Heat exhaustion is caused by excessive loss of water and salt. Symptoms may include heavy sweating, weakness, dizziness, nausea, headache, diarrhea and muscle cramps.
Whether indoors or outside, heat exhaustion can also cause cramps, fainting, nausea, vomiting, diarrhea, rash or swelling in the hands and feet.
While extreme heat can put everyone at risk, health risks are greatest for seniors, infants, young children, people with chronic illness and people who work or exercise in the heat.
