A Guide to Heat-Related Illness
Sometimes, summer is quite literally too hot to handle. Which is to say, heat can compromise your body’s ability to take care of itself and cause health complications. To put it simply: When it’s too hot or humid, your body can’t adequately cool off.
Sweating is the primary way your body cools itself down. It helps your body release heat and reach a cool, healthy temperature. However, sweating is only truly effective as a means to regulate body temperature when sweat can evaporate. When it doesn’t, your body can overheat, resulting in a heat-related illness.
Extreme heat is responsible for, on average, 658 deaths a year and while extreme heat is generally considered temperatures over 100 degrees Fahrenheit, your body can be at increased risk for heat illness anywhere above 90 degrees. Temperatures that are unreasonably hot for your climate, and that your body is therefore unused to, can also impact your risk for heat illness. Furthermore, humidity is no small factor. High humidity makes it harder for sweat to evaporate and, as previously established, it’s the evaporation, not sweating itself, that cools the body and releases heat.
Heat-related illness takes five primary forms, outlined below: sunburn, heat rash, heat cramps, heat exhaustion and heat stroke.
Sunburns might be the most commonly experienced form of heat illness, but should by no means be underestimated. Caused by too much exposure to UV rays from the sun, sunburns result in a red, painful skin burn after as little as 15 minutes and can increase your risk for skin cancer in the long term.
Sunscreen is the primary form of sunburn prevention and should be worn everyday and reapplied every two hours when you’re out in the sun. That said, it is not the only form of sun protection. Hats, light clothing, sunglasses and umbrellas are just a few items you should combine with your sunscreen habits.
Extreme sunburns can occur along with sun blisters or sun poisoning. In their most extreme, severe sun blisters can occur along with fever, chills, nausea or vomiting and should be treated by your primary care physician. Sun poisoning is an allergic reaction to the sun that may be the result of a bad sunburn. In addition to the symptoms of sunburn (pain, blisters), sun poisoning is marked by itchy bumps and can also include fever, chills, nausea and dizziness. An over-the-counter pain reliever and cortisone cream, as well as cool compresses, can help relieve pain, but if you’re experiencing more serious symptoms (blistering, nausea, fatigue), you should see your primary care physician or a dermatologist as soon as possible.
Excessive sweating can result in a rash of small red bumps called heat rash. When sweat doesn’t evaporate, it blocks the sweat glands and results in heat rash. As such, it’s most likely to occur on the neck, upper chest, in elbow creases and under the breasts or in the groin. It’s most common in tropical and humid climates and usually seen in infants.
Loose-fighting clothing can help prevent heat rash, as can spending time in cool or air-conditioned areas. Keeping the irritated area dry is the primary form of treatment, though lotion or dusting powder may be used to help with comfort.
Painful muscle cramps in the legs, arms or abdomen, known as heat cramps, may be the first sign of a serious heat-related illness and can be a symptom of heat exhaustion or heat stroke. Heat cramps occur most often after exercise in hot environments. People are likely to sweat more than usual in the heat, which can worsen dehydration and salt depletion. Salt depletion occurs when sodium levels in the body fall below normal, often caused by the rapid loss of fluids and electrolytes during intense physical activity. Low salt levels diminish your body’s ability to regulate fluids and cause cramps, while dehydration contributes to salt depletion as well as increases your risk for heat illness.
Heat cramps can be prevented by working out indoors or increasing fluid intake when outside. If you or someone near you experience heat cramps, rest immediately and avoid resuming activity for a few hours. Drink something high in electrolytes, such as a sports drink, while stretching lightly and massaging the affected muscles to relieve the spasm.
Dehydration can also cause heat exhaustion, an illness that can develop either quickly or gradually over a few days. Heat exhaustion happens when body temperature rises to 104 degrees or higher.
Symptoms of heat exhaustion include
- Excessive thirst
- Heavy sweating
- Cool, pale, clammy skin
- Fast, weak pulse
- Possible muscle cramps, including heat cramps
- Nausea or vomiting
If you or someone near you is experiencing heat exhaustion, find a cool, preferably air conditioned space and loosen any tight clothing. Provide water or a drink with electrolytes and apply cool, wet cloths to as much of the body as possible.
Left untreated, heat exhaustion can escalate into heat stroke. Simply put, heat stroke is your body’s most severe reaction when body temperature rises, sweating mechanisms fail and your body overheats. It can happen within 15 minutes of being in the heat and can cause death or permanent disability.
In addition to certain shared symptoms with other heat illnesses – dehydration, high body temperature, red or hot skin – heat stroke can affect your mental state as well. Hallucinations, disorientation, confusion, fogginess or dizziness and a loss of consciousness can all be signs of heat stroke. Meanwhile, other physical symptoms include a throbbing headache, nausea, shallow breathing, and a rapid and strong pulse.
Notably, absence of sweating is a key sign of heat stroke and the pulse is strong rather than weak like with heat exhaustion.
Heat stroke is a medical, life-threatening emergency. If you or someone around you appears to be suffering from heat stroke, call 9-1-1 immediately. Meanwhile, move to a shady or cool area and attempt to cool the person down however possible.
Keep Your Cool
Loose fitting clothing and staying in the shade can help you stay cool in the heat. If you can’t avoid the sun, drink water often and always wear sunscreen.
Your ability to tolerate the heat is dependent upon many factors. Age, obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, medications and alcohol can all affect whether you stay cool in the hot weather.
So, when the temperature rises, take precautions:
- Schedule your outdoor time and activities.
- During heat waves, spend as much time in air conditioning as possible.
- Wear lightweight, light-colored clothing.
- Take cool showers.
- Drink more water than usual.
- Don’t wait until you’re thirsty to rehydrate.
- Pace yourself, slowing down whenever needed.
- Check on your friends, neighbors and those at risk.
- Stay aware of heat advisories.
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