Danielle was enjoying an afternoon outside with her children. They’d gone to the park to play on the slide and the swings, and she’d brought along some sandwiches and other goodies for lunch. The food and drinks rested safe in a cooler under a tree while Danielle pushed one child and then the next, and then tried to catch each one in a game of tag.
They’d been out in the sun for about a half-hour when Danielle started to feel funny. When she looked at the trees, they were spinning around, and she had a sudden urge to lie down. She was also sweating a lot, and felt a little nauseated. She made her way to the cooler and drank some water while resting in the shade. Though she recovered enough to enjoy lunch with the kids, she didn’t feel right for the entire rest of the day.
Danielle later learned that she had suffered from heat exhaustion. The temperature had been over 90 degrees that day, and when she talked to her doctor about it, she realized that she had taken an antihistamine that morning to control her allergy symptoms. Her doctor informed her that antihistamines were one of several medications that could increase risk of heat illness, something she hadn’t been aware of.
Another thing Danielle didn’t know was that in general, women are more at risk for all types of heat illness, including heat exhaustion and heat stroke, as their bodies are less tolerant of higher temperatures. Though in most cases women can recover, heat illness can have serious complications, including life-threatening ones.
What is Heat Illness?
Anytime you’re exposed to prolonged or abnormal amounts of heat and humidity without a break—or without adequate hydration—you are at risk for a variety of different types of heat illness, or “heat emergencies” as they are sometimes called.
A heat illness occurs when you start to suffer health issues caused by excess heat. The heat may come from the environment you’re in, from intense exercise, or a combination of the two. These issues can range from a mild feeling of discomfort and fatigue to a major life-threatening event. In general, doctors tend to classify heat illnesses in four different categories.
These categories aren’t necessarily related to each other. You can experience heat stroke, for example, without going through heat cramps or heat exhaustion first. You may also have heat exhaustion without heat cramps. But the following heat illnesses are listed in general terms of severity, with heat stroke being the most serious of the four.
1. Heat Cramps
These typically occur during intense exercise and/or exercise in warm temperatures. They are muscle cramps and spasms that are caused by heat illness, typically because the person is slightly or more seriously dehydrated. They are also more likely when you’re first starting training, before your body has become conditioned to your new exercise routine.
Drinking water or something like Gatorade that replenishes electrolytes typically solves the problem, along with resting and stretching the muscle.
2. Heat Fainting (Syncope)
Also called “orthostatic dizziness,” heat fainting is when someone actually passes out of heat illness. It’s most common at the start of summer, when people haven’t yet adapted to the heat, and occurs because of a lack of adequate blood flow to the brain. That means that you’re more at risk when you’re standing for long periods of time without moving, or when you stand up suddenly after sitting or lying down. Dehydration also increases risk.
People usually recover from heat fainting within 10-15 minutes. It helps if others move the affected person to the shade, elevate the legs, cool with compresses and fanning, and monitor vital signs to be sure nothing else goes wrong. As soon as the person wakes up, it’s best that they drink water or a sports beverage to rehydrate.
The exception to the rule is if the person fainted because of heat stroke. Then medical attention is needed right away. If the person was exercising or working hard before the fainting occurred, this is more likely to be the situation.
3. Heat Exhaustion
This is the most common type of heat illness, and is typically more serious than the first two. It’s common in athletes and recreational hikers, and also more frequently hits vulnerable people like those over 65 years, pregnant and nursing moms, people who are taking certain medications, and people who are battling other illnesses. Babies and children are also more at risk.
Heat exhaustion occurs when the body gets hotter than it should. If you notice symptoms of heat exhaustion, it’s important that you take care of it right away before it gets worse.
Like other heat illnesses, heat exhaustion is caused by exposure to warm temperatures, potentially combined with high humidity, and often brought about by physical exertion. The body loses too much water and electrolytes through sweating that aren’t replaced by drinking. Age, medications, and other factors can also interfere with the body’s ability to regulate it’s own temperature, or to adapt to the warmer air.
The body systems become overwhelmed, to the point they produce more heat than they can release. Symptoms include:
- Pale, clammy skin
- Rapid heartbeat
- Dizziness, fainting
- Nausea and/or vomiting
- Muscle weakness or cramps
If you feel these symptoms, you want to immediately stop what you’re doing, get to a cooler location, and rest. Drink cool water or something like Gatorade that will replace electrolytes, elevate your legs to ease blood flow to the heart, remove any unnecessary clothing, and if you can, get some cool water on your skin. A cool shower or bath will help.
These steps should have you feel better shortly. If you’re still suffering the same intensity of symptoms after an hour has passed, seek medical help right away.
4. Heat Stroke
Heat stroke is the most serious type of heat illness, and if not treated properly and immediately, can be fatal. It’s similar to heat exhaustion as it occurs when the body is overwhelmed by heat and can no longer regulate its own temperature. Again, it’s caused by hot air, humidity, and physical exercise, combined with a lack of hydration, and can be more likely in vulnerable populations.
Also called “sunstroke,” heat stroke is defined as occurring when the body temperature rises above 40 degrees Celsius (104 degrees Fahrenheit). Because of the high temperatures, some of the body’s internal systems start to shut down. Some organs may suffer damage unless the body temperature is reduced quickly. Untreated heat stroke can also lead to heart, kidney, brain, and muscle damage.
Symptoms of heat stroke include:
- High body temperature (104 degrees Fahrenheit)
- Nausea and vomiting
- Rapid breathing and heart rate
- Abdominal cramps and muscle cramps
- Flushed skin
- Throbbing headache
- Confusion, agitation, slurred speech
- Loss of consciousness
Treatment for heat stroke is similar to treatment for heat exhaustion, except that you need to call emergency help immediately. Remove excess clothing and try to get the person cooled down as quickly as possible—immersing in cold water is the best approach. If there is no tub or shower nearby, use ice-cold wet towels over as much of the body as possible. Monitor vital signs and wait for emergency technicians.
When treated immediately, people with heat stroke typically recover completely.
How Do I Tell if it’s Heat Exhaustion or Heat Stroke?
You may wonder about the similarities between heat stroke and heat exhaustion. There are a few key differences you can watch out for. Remember that if you see signs of heat stroke, you need to get emergency help.
- Heat exhaustion causes a lot of sweating, whereas during heat stroke, sweating stops and the person’s skin may be dry. (Not always the case, but often.)
- Heat stroke is accompanied by a high fever, which is less likely in heat exhaustion.
- Heat stroke affects the central nervous system, which affects behavior. You’ll notice irritability, emotional instability, altered consciousness, irrational behavior, and other similar symptoms that don’t occur with heat exhaustion.
- Headaches are usually more severe with heat stroke.
Both conditions can develop gradually or suddenly, but in most cases, you will notice signs like fatigue, weakness, dizziness, and a general feeling of being sick or unwell as the condition develops.
Preventing Heat Illness This Summer
If you’re taking any medications at all, be sure to check with your doctor to see if they may increase your risk of heat illness. If you’re struggling with another health issue, even if it’s only high blood pressure, realize that it increases your risk of heat illness and take appropriate precautions.
Once you’ve suffered a heat illness, you may be prone to suffering another, so don’t be surprised if you need to be extra careful. No matter who you are, though, heat illness can affect you, so follow these tips whenever you’re out in the warm weather:
- Stay hydrated: This is key to helping your body adapt to the heat. Follow the half-half rule—drink ½ liter of water (a little over two eight-ounce cups) every half hour. If you’re exercising or working, it’s best to drink a sports drink with electrolytes added to help replace those you lose through sweating.
- Accept your risks: Realize that if you are a woman, you’re more at risk for heat illness. Medications, cardiovascular issues (like high blood pressure), overweight and obesity, fitness level, and age can also increase your risk. Be aware of your own personal response to heat and act accordingly.
- Wear lightweight clothing: This may seem like common sense, but sometimes we can forget that we need loose-fitting, moisture-wicking clothes if we’re going to be exercising or working in warm temperatures. Cotton may not the best choice, for example, as it can become sopped with sweat and then tends to keep it in rather than allowing it to dissipate. Look for fabrics that are made to keep you cool.
- Practice avoidance: If it’s super hot outside, don’t push your luck, especially between the hottest hours of 11:00 a.m. to 3:00 p.m. Scout out any outdoor events to be sure you’ll have access to shade and water. Wear wide-brimmed hats and sunglasses, and take an umbrella along. Avoid any dangerous situations.
- Plan ahead: If you want to exercise or work outdoors, plan it during the cooler times of the day, such as early morning or later evening.
- Rest: If you must work in the heat, take frequent breaks to let your body rest and recover. Ideally, rest in cooler, shaded areas.