Heat Exhaustion vs. Heat Stroke: What’s the Difference? 

Summer comes with warm, sunny days that usher many people outdoors, but higher-than-usual temperatures and extreme heat can cause health concerns.  

“During the summer months, we see a lot of patients with heat-related illnesses,” Afsoun Sichani, MD, Medical Director of WVU Medicine Urgent Care-East, said. “Sometimes I hear people using heat stroke and heat exhaustion interchangeably, but these are very different conditions that require different treatment.” 

Heat-related illnesses are a spectrum, and if a person’s condition progresses to heat stroke, it is an emergency, according to Ben Deuell, DO, WVU Medicine Emergency Medicine Specialist. 

“Heat stroke is the most severe level of heat-related illness is life-threatening, requiring emergent medical stabilization to prevent further deterioration,” Dr. Deuell said.  

Here are some insights about the differences between heat stroke and heat exhaustion, and what you can do if you experience them this summer. 

Heat Exhaustion 

Heat exhaustion happens when your body can’t cool itself through sweating. It often happens after other signs of overheating like heat rash or cramps, but before a heat stroke. 

“Anyone can develop heat exhaustion, especially in the hot summer weather,” Dr. Sichani said. “Children and the elderly are often at a higher risk. And if you’re exercising outdoors or dehydrated, that can make you more susceptible to heat exhaustion or worse.” 

Signs of heat exhaustion to watch for include: 

• Body temperature between 101-104 degrees Fahrenheit.
• Pale skin.
• Dizziness, weakness, or fatigue.
• Rapid breathing and increased heart rate.
• Headaches, nausea, vomiting 

“Get out of the heat as quickly as possible and try to cool yourself down,” Dr. Sichani said. “If you are stable and alert, but your condition isn’t improving, you can visit Urgent Care. If you’re struggling to stay alert or your symptoms are getting worse, you may have crossed into heat stroke territory, which is an emergency.” 

Heat Stroke 

Heat stroke means your body temperature is climbing too quickly to dangerous levels and the body’s cooling mechanisms – like sweating – get overwhelmed and stop working.  

“Without proper, prompt treatment, heat stroke can be fatal,” Dr. Deuell said. “If your heat symptoms have progressed, call 911 or come to the emergency department as quickly as possible.” 

Symptoms of heat stroke include: 

• Body temperature above 104 degrees Fahrenheit.
• Dizziness, fainting, slurred speech.
• Altered mental state including agitation, confusion or loss of consciousness
• Dry, red skin and may have an inability to sweat.
• Rapid pulse.
• Seizures. 

“The good news is; heat-related illnesses and emergencies can often be prevented,” Dr. Deuell said. “Stay hydrated, avoid strenuous exercise during peak heat, and watch for the early signs of overheating and heat exhaustion.” 

 Find our WVU Medicine Urgent Care locations near you in the Eastern Panhandle region, and learn more about our Emergency Departments at WVU Medicine Berkeley and Jefferson Medical Center.

Featured Experts

Drs. Ben Deuell, DO, and Afsoun Sichani, MD