The human body is designed to operate within a fairly narrow temperature window and has internal systems in place to maintain that temperature. However, when the temperature outside is high, and especially when we’re active (working or playing) outside when it’s hot, those internal systems can break down, and the body can suffer from several different kinds of heat illnesses.

When we first start getting overheated, our blood vessels get bigger and our hearts start to beat harder and faster to pump blood to the outer layers of the skin, where the heat can be released. If that doesn’t cool our bodies fast enough or if the air is warmer than our skin, we start sweating in an attempt to cool off through evaporation. These mechanisms can be very effective… if there’s a breeze and if the humidity isn’t too high for evaporation to work properly. However, they also draw blood away from the brain and other vital internal organs and remove water and salts from the blood (we can easily sweat out a whole quart of water over an hour of hard work in hot weather), and if we don’t take steps to rest and rehydrate, we can become dehydrated and the system can break down, resulting in a dangerous increase in body temperature.

Heat illnesses can develop very rapidly and it’s not always obvious what’s happening before it becomes life-threatening. Know the signs and symptoms and how to prevent yourself and others from suffering severe consequences from heat exposure.
 

Mild heat illnesses

-  Heat rash – caused by excessive sweat blocking sweat glands, heat rash symptoms include red, itchy skin, tingling or “prickly” pain, and small bumps or blisters where skin touches itself or stays wet when you sweat. Treatment includes drying off, cool compresses, and not applying any products that block your pores. Seek medical treatment if the symptoms don’t improve after three days.
-  Heat cramps – caused by excessive sweating, which depletes the body’s stores of necessary electrolytes and fluids, causing generalized weakness and diffuse muscle cramping and spasms. Treatment includes drinking water and electrolyte solutions and resting.

Severe heat illnesses

Heat Exhaustion

Symptoms

·  Heavy sweating and thirst
·  Muscle cramps
·  Extreme weakness and/or fatigue
·  Nausea and/or vomiting
·  Dizziness and/or headache, irritability, anxiety
·  Elevated body temperature and heart rate
·  Clammy, pale, cool, and/or moist skin
·  Quick, shallow breathing
·  Quick, weak pulse
·  Decrease in urination
·  Dizziness, weakness, lack of coordination, fainting

What to do

·  Move the person to a cool, shaded area
·  Wet down their skin with cool cloths
·  Get them to drink small sips of cool water and/or an electrolyte drink
·  Call 911 or take them to Urgent Care. Especially if they’ve gotten to the dizziness/fainting/lack of coordination stage, they need to be checked out by a medical professional
 

Heat Stroke

Symptoms

·  Not sweating (this mechanism has completely broken down due to dehydration)
·  Hot and dry skin (may be red, bluish, or mottled)
·  Muscles may twitch uncontrollably
·  Rapid pulse and quick, shallow breathing
·  Headache
·  Nausea
·  Body temperature may range from 102° - 104° F or higher
·  Slurred speech, confusion, agitation, hallucinations
·  Seizures
·  Unconsciousness, coma

What to do

·  Call 911 immediately – this is a life-threatening emergency that can lead to organ failure and death
·  Move the person to a cool, shaded area
·  Wet down their skin with cool cloths
·  Put ice packs on armpit and groin areas (big blood vessels are close to the surface there, so the cooling can reach the blood faster)
·  Do not give them any liquids (at this point, they need intravenous fluids, not something they can easily choke on or breathe in)

Factors that increase your risk of suffering from a heat-related illness include:

·  Dehydration – if you start out dehydrated, your temperature regulation system breaks down even faster. Remember that we already need more water to stay hydrated at higher altitudes (like in Crystal Lakes) and adjust your intake accordingly.
·  Obesity, poor physical fitness, or lack of experience working in a hot environment.
·  Taking certain prescription medications, including tranquilizers, water pills, antihistamines, beta blockers, laxatives, and some drugs used to treat mental illnesses.
·  Using alcohol or mind-altering substances.
·  Certain medical conditions, such as diabetes, kidney problems, heart problems, high blood pressure, and pregnancy.
·  Age – those under 4 or over 65 are at higher risk.
·  A prior history of heat-related illnesses – once you’ve experienced a heat-related illness, your body is more susceptible to having it happen again.
 

How to avoid heat-related illnesses

·  Stay in the shade and/or cooler areas whenever possible
·  Take frequent breaks to cool off in the shade and rehydrate
·  Drink plenty of water. Don’t wait until you’re thirsty – by the time you’re thirsty, you’re already dehydrated. (The best advice is to drink water at least every fifteen minutes, whether you’re thirsty or not.)
·  Avoid alcohol, caffeinated drinks, and large amounts of sugary drinks.
·  Wear a hat and lightweight, light-colored, loose-fitting clothing.
·  Wear sunscreen – a sunburn reduces your body’s ability to cool down via its usual mechanisms and can also dehydrate you.
·  Rest often.

The following graphic, provided by the Larimer County Public Health Department, is an excellent reminder of how to tell the difference between the two most dangerous forms of heat-related illnesses and what to do about them.

We all enjoy our gorgeous mountain summers, but make sure you’ve got plenty of water, rest often, take advantage of shade, and keep an eye on yourself and your friends and family – make sure everyone is working or recreating safely and not sliding into a heat illness that could have serious consequences.

Copyright: Crystal Lakes Volunteer Fire Department, 2025