Hypothermia occurs when the human body is exposed to freezing temperatures, such as in cold weather or water. The condition arises due to the body losing heat faster than it can produce it. Low body temperature can prove fatal if they are not corrected. Hypothermia progresses in three stages: mild, moderate, and severe. In the first stages, you may not be aware that anything is wrong, which is why it’s important to know the symptoms of hypothermia, particularly if you spend a lot of time in the cold.

Shivering

We all shiver when we feel cold, as this is one way the body generates heat. However, shivering is also one of the first and most common signs of mild hypothermia. If the bout of shivering appears to be at a normal rate but gets increasingly violent over time, this could point to hypothermia. Eating something sugary when you start shaking can ease it somewhat. If extreme shivering suddenly stops, the body temperature may still be dropping, and the hypothermia could become more severe.

Hunger

Some people with hypothermia report unexplained hunger. As the body temperature continues to drop, however, they may not want to eat anything at all. Hypothermia also robs the body of its senses. If this happens, there will be far less energy to warm up the body. To avoid hypothermia, you should always make sure to eat something while you are out in the cold.

Fatigue

Gradual sleepiness is a sign of mild hypothermia. At first, you may just feel slightly lethargic, but as the condition progresses you may also begin to feel drowsy. If you’re with someone who is exhibiting these symptoms, move them out of the cold, lie them down somewhere warm, if possible, and monitor their breathing.

Confusion

When body temperatures drop below normal levels, the brain stops working efficiently. This can be a difficult symptom for the person experiencing hypothermia to notice. Slower reactions and impaired judgment are signs that hypothermia is setting in. If you can, try to insulate the person from the cold ground with the use of a blanket or other warm surface. Warm, non-caffeinated beverages may also help regulate body temperature.

Slurred Speech

Slowed or slurred speech is another sign of progressing hypothermia. Once again, the person who is experiencing it may not be aware it is occurring. If the person you are with starts to slur when they speak or appear unresponsive, their temperature may be drastically low. Make sure to get them out of their cold clothes and into the warmth and call 911. If no change of clothes is available, skin-to-skin contact and blankets will work almost as well.

Weak Pulse

A weak pulse is a sign the heart rate is decreasing. Usually, a weak pulse means there is a serious problem somewhere in the body, and when in cold temperatures, the onset of severe hypothermia is the most likely cause. This is the stage at which it becomes vital to get medical attention. If the person you are with is showing symptoms of hypothermia, call 911.

Shallow Breathing

In mild instances of hypothermia, respiratory rates may increase. This is part of the body’s physiological response to cold, an attempt to preserve heat. The more severe the hypothermia gets, the shallower and slower the breathing will become. If a person with suspected hypothermia is not breathing properly or is unconscious, continue trying to warm them up and consider administering CPR.

Clumsiness

Most of the time, hypothermia looks a lot like intoxication. Scientific American has even compared the signs of hypothermia to how someone may present when they are in a “drunken stupor.” Symptoms such as confusion and poor motor function can cause a person to stumble when they walk and mumble when they speak. If someone you know is appearing drunk after a prolonged period in cold weather, get them to shelter.

Pale Features

At the moderate stage of hypothermia, the person’s skin and lips may appear pale or blue. Their skin may also feel icy cold to the touch. As the body focuses its remaining energy on keeping vital organs warm, the surface blood vessels will contract further.

Loss of Consciousness

Once the body temperature sinks below 86 °F, the pale skin may also start to appear puffy. As the pulse and respiration rates decrease significantly, the person can seem disoriented and exhibit irrational behavior. They may also stop breathing. An unconscious person with hypothermia may experience organ failure and cardiac arrest.