Hypothermia occurs when the body gets cold and loses heat faster than
the body can make it. A normal rectal body temperature ranges from
97.5°F (36.4°C) to
99.7°F (37.6°C) and for most
people is 98.6°F (37°C) by
mouth and 99.7°F (37.6°C)
rectally. Hypothermia is more likely to occur when you are exposed to cold air,
water, wind, or rain. Hypothermia can occur indoors, especially in babies and
older or ill adults that are not dressed warmly enough.
A rectal temperature is considered the most
accurate body temperature. For information on how to take an accurate
temperature, see the topic
Emergency care needed
Hypothermia is an emergency condition and can quickly lead to
unconsciousness and death. Hypothermia can occur at temperatures of
50°F (10°C) or higher in wet
and windy weather, or if you are in
60°F (16°C) to
70°F (21°C) water.
Mild hypothermia: Rectal temperatures between
90°F (32°C) and
Moderate to severe hypothermia: Rectal temperatures
below 90°F (32°C)
To help remember the signs of hypothermia, learn the "umbles" phrase,
which is "stumbles, mumbles, fumbles, and grumbles." These words describe
changes in a person's physical coordination and mental alertness that may be
the first signs of hypothermia.
Cold, pale, or blue-gray
Lack of interest or concern (apathy)
Mild unsteadiness in balance or
Numb hands and fingers and
difficulty performing tasks
Shivering may stop if body temperature drops
below 90°F (32°C).
It is very important to get treatment for hypothermia quickly.
Often a hiker or skier will lose heat to a critical temperature before others
notice anything is wrong. If someone begins to shiver violently, stumble, or
can't respond to questions, suspect hypothermia and warm them quickly.
Medical treatment for hypothermia depends on the severity of the
hypothermia. Treatment of mild hypothermia includes getting out of the cold or
wet environment, using warm blankets, heaters, and hot water bottles.
Moderate to severe hypothermia generally is treated in the
hospital, where health professionals can give warmed
intravenous fluids and warm, moist oxygen in addition
to other treatments to warm the core body temperature.
Most healthy people with mild to moderate hypothermia recover
completely without permanent injury. Recovery is more difficult for babies and
older, ill, or inactive adults.
How this information was developed to help you make better health decisions.