Heat-Related Illness: The Difference Between Heatstroke and Heat Exhaustion

Heat exhaustion and heatstroke are types of heat-related illnesses. The spectrum of heat-related illnesses includes heat rash, heat cramps, heat exhaustion, and heatstroke.

Warning Signs

Sweating is your body’s way of cooling itself down. On hot, humid days, especially if you’re exercising or doing physical work in hot weather, sweating might not be enough. Heat exhaustion and heatstroke both cause your body temperature to rise. The temperature spike goes hand in hand with several other symptoms.

Heat exhaustion symptoms

• High body temperature.
• Rapid breathing and heart rate.
• Muscle cramps.
• Headache.
• Dizziness or lightheadedness.
• Pale skin.
• Nausea and vomiting.
• Weakness and fatigue.

Heatstroke symptoms

• Confusion or agitation.
• Hallucinations and an altered mental state.
• Inability to sweat.
• Dry, red skin.
• Dizziness or fainting.
• Slurred speech.
• Very high body temperature (more than 40 degrees celsius).

Populations disproportionately affected by heat include:

• Older adults and children
• Those who are pregnant
• Athletes and outdoor workers
• People with cardiovascular illnesses, obesity, diabetes, respiratory illnesses, renal disease, neurological disease, and health health disorders including addictions
• People who are malnourished or dehydrated
• People who have a history of heat illness or an active sunburn
• People who live alone or are socially isolated
• People with lower socioeconomic status
• Those who live in cooler climates and are poorly adapted to heat.

How to avoid heatstroke and heat exhaustion

Even when it’s sweltering outside, there are ways to stay safe. 

• Drink up: Dehydration increases the risk of heat-related illness, so drink plenty of water when the temperature increases.
• Take a break: Most cases of heat exhaustion and heatstroke occur when people are exercising or working outside in hot conditions. If possible, avoid intense exercise and long stretches of activity on hot, sunny, or humid days.
• Cool off: If you notice signs of heat exhaustion, get to a cool area immediately – Ideally into the air conditioning, but at least into the shade.
• Pay attention:Be aware of others around you. People don’t always recognize the signs of heat illness in themselves. So if you notice symptoms in others, help them get to a cool, shady place. If symptoms get worse, seek medical attention.

Get cool: Heat exhaustion and heatstroke treatment

If you have any signs of heat exhaustion, get out of the heat as quickly as you can. Drink water to rehydrate and take steps to bring down your body temperature. To help cool your body, you can apply ice packs to the neck, armpits and groin. You can also run cool water over yourself (such as your wrists) to help you cool down.

If you continue to feel sick — or notice signs of heatstroke, especially neurologic symptoms such as confusion, stumbling or clumsiness — call 911 or seek urgent care.

Health Risk Factors Associated with Medications

There are some drugs that are known to interfere with the body’s temperature regulation mechanisms or hydration status, predisposing people to heat illness. Some examples of drug classes include:

• Antipsychotics/Neuroleptics
• Antidepressants
• Lithium
• Anti-epileptics
• Anti-Parkinson’s Agents
• Diuretics
• Nitrate vasodilators
• ACE inhibitors
• Calcium channel blockers & beta blockers

If you are on any of these medications and/or you have questions about heat-related illnesses, your Personal Pharmacist is here to help. Please ask us for more information or a personalized plan. We are here to help.