Hypothermia occurs when your body loses heat faster than it can produce heat and your body temperature falls below 95 F (35 C). Left untreated, it can be life-threatening.

Hypothermia is often caused by exposure to cold weather or immersion in a cold body of water. It can also be caused by ongoing exposure to indoor temperatures below 50 F (10 C). You could be at increased risk if you're also exhausted or dehydrated.

Signs and symptoms of hypothermia usually develop slowly and may include:

  • Shivering, though this may stop as body temperature drops
  • Slurred speech or mumbling
  • Slow, shallow breathing
  • Weak pulse
  • Clumsiness or lack of coordination
  • Drowsiness or very low energy
  • Confusion or memory loss
  • Loss of consciousness
  • Bright red, cold skin (in infants)

Seek emergency medical care

If you suspect someone has hypothermia, call 911 or your local emergency number. Then immediately take these steps:

  • Gently move the person out of the cold. If going indoors isn't possible, protect the person from the wind, especially around the neck and head. Insulate the individual from the cold ground.
  • Gently remove wet clothing. Replace wet things with warm, dry coats or blankets.
  • If further warming is needed, do so gradually. For example, apply warm, dry compresses to the center of the body — neck, chest and groin. The CDC says another option is using an electric blanket, if available. If you use hot water bottles or a chemical hot pack, first wrap it in a towel before applying.
  • Offer the person warm, sweet, nonalcoholic drinks.
  • Begin CPR if the person shows no signs of life, such as breathing, coughing or movement.

Caution

  • Do not rewarm the person too quickly, such as with a heating lamp or hot bath.
  • Don't attempt to warm the arms and legs. Heating or massaging the limbs of someone in this condition can stress the heart and lungs.
  • Don't give the person alcohol or cigarettes. Alcohol hinders the rewarming process, and tobacco products interfere with circulation that is needed for rewarming.

Mayo Clinic Minute: Why the risk of frostbite is greater than you think

As winter drags on and temperatures drop way down, your risk of cold-related injury like frostbite can go way up.

"Literally think of it as freezing of the tissues," Dr. Sanj Kakar Mayo Clinic Orthopedic hand and wrist surgeon says frostbite is more common than many people think.

"We tend to see frostbite, for example, when the temperature is 5 degrees Fahrenheit with minimal windchill," Dr. Kakar explains.

If the windchill drops below negative 15 degrees Fahrenheit, not unheard of in the northern half of the U.S., frostbite can set in within half an hour.

The most vulnerable areas of frostbite are your nose, ears, fingers and toes.

"Initially [with] the milder forms, you can get some pain and some numbness of the tips, but the skin can change its color," Dr. Kakar says. "It can be red. It can be white. Or it can be blue. And you can get these blisters on your hands. And it can be a very serious injury."

The worst cases, the tissue can die, and you may need surgery to remove it.

So who's most at risk?

"[Those most at risk are] certain patients with diabetes, patients who have previous history of frostbite are prone to it, the elderly or your very young children, and also, for example, if you're dehydrated," he says.

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April 16, 2022