Heat Wave Safety: Expert Tips to Avoid Heat Illness

As temperatures rise, so does the risk of heat-related illnesses such as sun poisoning, heat exhaustion, and heat stroke.

“Heat-related illness can happen faster than people realize, especially in extreme temperatures or during increased activity,” says Adam D. Blumenberg, MD, an emergency medicine physician and medical toxicologist at Columbia. “The good news is that most cases are preventable with the right precautions.”

Dr. Blumenberg explains what you can do to protect yourself during periods of extreme heat and dangerous heat waves.

Who is most at risk of heat-related illness?

Extreme heat is especially dangerous for the young, the elderly, pregnant women, people with heart conditions, and those taking certain medications (such as antihistamines, some antidepressants, and diuretics).

“Certain medications and underlying conditions can make it harder for the body to regulate temperature,” Dr. Blumenberg says. “That’s why some people are more vulnerable than others in extreme heat.”

In a heat wave, it's essential to recognize the symptoms of heat-related illnesses such as heat exhaustion and heat stroke.

What are the symptoms of heat exhaustion?

Heat exhaustion occurs when your body overheats because of high temperatures and dehydration. Common signs and symptoms of heat exhaustion include:

• Excessive sweating
• Fatigue or weakness
• Dizziness or lightheadedness
• Headache, nausea, or vomiting
• Muscle cramps
• Rapid heartbeat
• Feeling faint or near-fainting

“Heat exhaustion is your body’s warning sign,” Dr. Blumenberg says. “If you notice these symptoms, it’s important to stop, cool down, and hydrate right away.”

Taking these immediate actions is critical to preventing heat exhaustion from progressing to heat stroke.

What are the symptoms of heat stroke?

Heat stroke is a true medical emergency that can be life-threatening or cause permanent damage to internal organs such as the kidneys and liver. The symptoms of heat stroke may include:

• High body temperature (above 103°F or 39.4°C)
• Altered mental state or confusion
• Throbbing headache
• Rapid and shallow breathing
• Racing heart rate
• Red, hot, and dry skin
• Nausea, vomiting, or diarrhea
• Seizures
• Loss of consciousness

“Heat stroke can become life-threatening very quickly,” Dr. Blumenberg says. “If someone is confused or collapses, seek emergency care immediately.”

Heat stroke can develop within a few hours of exertion or physical activity in extreme heat, or it can develop without exertion over a few days in a hot place, such as an unairconditioned apartment.

How do you prevent heat exhaustion?

Extreme heat requires special precautions to prevent conditions such as heat rash, sunburn, heat exhaustion, or heat stroke. Here are some tips for staying safe in hot weather:

• Time your activities wisely: Do outdoor activities like hiking during the cooler parts of the day, such as early morning or evening. “If possible, avoid peak heat hours and build in time to rest,” Dr. Blumenberg says.
• Stay hydrated: Drink plenty of fluids like water. Avoid excessive amounts of alcohol, caffeine, and sugary drinks, as they can contribute to dehydration.
• Dress light: Wear lightweight, loose-fitting, light-colored clothing that protects your skin from direct sunlight. Consider a wide-brimmed hat and sunglasses to shield your face and eyes. “Lightweight, breathable clothing helps your body regulate temperature,” Dr. Blumenberg says.
• Apply sunscreen: Use a broad-spectrum sunscreen with a high SPF (Sun Protection Factor) to protect your skin from harmful UV rays. Reapply it every two hours or more frequently if you're sweating or swimming.
• Seek shade: Find shade or take breaks indoors to cool down. If you're in a location without natural shade, use an umbrella or set up a canopy to create your own shade.
• Use cooling aids: Carry a portable fan and use a cooling towel. You can also wear a damp bandana around your neck to help lower your body temperature.
• Pace yourself: Take regular breaks and listen to your body. If you feel tired, dizzy, or experience heat-related symptoms, find a cool place to rest and recover. “Listening to your body is critical,” Dr. Blumenberg says. “Pushing through symptoms can make things worse.”
• Be mindful of food safety: Avoid consuming foods that spoil quickly in high temperatures, especially if you need clarification on their storage conditions. Choose light, fresh meals that won't weigh you down or feel heavy.
• Stay connected: Inform a friend or family member about your plans and check in with them regularly. Carry a fully charged mobile phone and keep emergency contact numbers handy.
• Visit a cooling center: When it comes to at-risk individuals such as seniors, “I would recommend that they go to cooling centers or another air-conditioned environment if their home is very hot inside,” says Blumenberg.

What is first-aid for heat-related illnesses?

If you suspect someone is experiencing heat exhaustion or heat stroke, call emergency services and take immediate steps to cool them down. Move them to a shaded area, apply cool water to their body, and fan them. If you are waiting for emergency medical services to arrive, you can also help cool their body by:

• Removing excess clothing
• Applying ice packs or cold compresses to the neck, armpits, and groin
• Monitoring vital signs by checking the person's breathing, pulse, and level of consciousness
• Offering small sips of cool water, if they are conscious and can swallow
• Providing reassurance and comfort

As summer heats up, remember that preventing a heat emergency is all about being prepared. “Early action can make a significant difference in preventing complications,” Dr. Blumenberg says.

Adam D. Blumenberg, MD, is an associate professor in Columbia's Department of Emergency Medicine.