During the summer months when the heat index rises and the weather gets hot and humid, exposure to extreme heat and humidity can lead to serious heat-related illness that everyone should avoid.
Heat-related illness happens when the body’s temperature control system becomes overloaded. The body sweats to cool itself down, but when the body is unable to adequately cool down by sweating, body temperature can rise rapidly and lead to illness and damage to the brain or other vital organs.
Most at risk for heat-related illness, such as heat stroke, heat exhaustion, heat cramps and heat rash, include:
- Infants and children up to four years of age.
- People 65 years of age and older.
- Those who are overweight.
- People who are ill.
- Those who take certain medications, such as diuretics, sedatives, heart and blood pressure medicines.
And yet, it’s important to remember that everyone is at risk for heat-related illnesses, so it is good for all people to be cautious in hot weather.
Heat stroke is the most serious heat-related illness. If body temperature rises to 106°F or higher within 10 to 15 minutes, heat stroke can cause death or permanent disability when emergency treatment is not provided. Warning signs of heat stroke vary but may include:
- High body temperatures (>103°F)
- Hot, red, dry or moist skin
- Rapid and strong pulse
- Feeling faint and/or fainting
Heat stroke is very serious. When someone experiences it, call 911 immediately, move him or her to a cooler environment, and try to reduce his or her body temperature with cool cloths or even a cool bath. If the person is conscious and alert, let him or her drink a beverage (without caffeine or alcohol) such as a sports drink or cool water with about a teaspoon of salt. Do NOT give fluids to someone who is unconscious or is losing consciousness, because doing so may cause them to choke.
Heat exhaustion is a milder form of heat-related illness that can develop after several days of exposure to high temperatures and inadequate or unbalanced replacement of fluids. Those most prone to heat exhaustion are elderly people, those with high blood pressure, and people working or exercising outside in hot weather. Signs of heat exhaustion may include:
- Heavy sweating
- Cold, pale, and clammy skin
- Fast, weak pulse
- Nausea or vomiting
If you are suffering from heat exhaustion, move to a cool location, lie down and loosen clothing, apply cool, wet cloths to as much of the body as possible, and sip water. If you vomit, seek emergency medical attention immediately, as it may be a sign of severe dehydration.
Exercise is a vital part of good health, but exercising in the heat requires extra caution. Heavy exercise or strenuous work in extremely warm weather can cause heat cramps. These painful muscle spasms can be intense and prolonged due to loss of fluid and electrolytes and can occur during or after activity in the heat. Muscles most often affected include the abdomen, arms and legs.
If you have heat cramps, stop what you’re doing, rest, and cool down, drink electrolyte-replenishing fluids (e.g., sports drinks, coconut water), gently stretch and massage the affected muscle(s), and wait for several hours or longer after heat cramps resolve. If your cramps continue for longer than an hour, call your doctor.
Hot and humid weather can cause excessive sweating, which can lead to a heat rash—i.e., skin irritation that may look like a group of red pimples or small blisters. They can occur around the neck, upper chest, elbow crease, groin, and under the breasts. It is more common in young children, though adults can have it as well. If you have heat rash, try to keep the skin cool and dry, and see a healthcare provider if it doesn’t go away in a few days.
When out and about in hot weather, help prevent heat–related illness by following these simple tips:
- Limit your outdoor activity to morning and evening hours when temperatures may be cooler.
- Drink plenty of fluids. Keeping hydrated is important as high heat and humidity can sap fluids from the body.
- Avoid sugary or alcoholic beverages.
- Stay indoors and, if at all possible, in an air-conditioned place.
- When temperatures are above 90 degrees, take cool showers or baths.
- Wear loose, light-colored, light-weight clothing.
- NEVER leave anyone in a closed, parked vehicle.
- Check in regularly on those at risk such as infants and young children, people older than 65 years, people with mental and/or physical illnesses.
Caroline Pak, PharmD, is a pharmacist and the Medical Editor-in-Chief for Pfizer’s Get Healthy Stay Healthy website.
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