Hypothermia is a dangerous drop in body temperature below 35C (95F). Normal body temperature is around 37C (98.6F).
Hypothermia can be serious if not treated quickly.
You should call 999 and give first aid if you notice signs of hypothermia.
Symptoms of hypothermia
Early signs of hypothermia include:
- shivering
- cold and pale skin
- slurred speech
- fast breathing
- tiredness
- confusion
These are symptoms of mild hypothermia, where someone's body temperature is between 32C and 35C.
If their temperature drops to 32C or lower, they'll usually stop shivering completely and may pass out.
This is a sign that their condition is getting worse and emergency medical help is needed.
Hypothermia in babies
Babies with hypothermia may look healthy, but their skin will feel cold.
They may also be limp, unusually quiet and refuse to feed.
Treating hypothermia
You should call 999 and then give first aid if you think someone has hypothermia.
First aid for hypothermia
To warm the person up:
- Move them indoors.
- Remove any wet clothing and dry them.
- Wrap them in blankets.
- Give them a warm non-alcoholic drink, but only if they can swallow normally.
- Give energy food that contains sugar, such as a chocolate bar, but only if they can swallow normally.
If the person cannot be moved indoors, find something for them to rest on to protect them from the cold ground, like a towel or a blanket.
If they do not appear to be breathing – and you know how to do it – give them CPR, but you must continue this until professional help arrives in the form of the ambulance service or a medical team.
Things to avoid
Some things can make hypothermia worse:
- do not put the person into a hot bath
- do not massage their limbs
- do not use heating lamps
- do not give them alcohol to drink
These actions can cause the heart to suddenly stop beating (cardiac arrest).
Causes of hypothermia
Hypothermia happens when your body gets too cold and your temperature drops below 35C.
Hypothermia can be caused by:
- inadequate clothing in cold weather
- falling into cold water
- getting cold in wet clothes
- living in a cold house
- being very tired and cold
Who's at risk?
Some groups of people are more vulnerable to hypothermia.
They include:
- babies and children – they lose heat faster than adults
- older people who are inactive and do not eat well
- heavy alcohol and drug users – their bodies lose heat faster
Preventing hypothermia
To stay warm indoors in cold weather:
- keep your home at a temperature of at least 18C
- a baby's room should be 16 to 20C
- keep windows and internal doors shut
- wear warm clothes
- use a room thermometer
Check in on an elderly neighbour regularly during cold weather to make sure their home is warm.
The government offers a winter fuel payment for older people to help them pay their heating bills.
Find out how to stay warm in cold weather
To stay warm outdoors:
- plan your activity
- plan for the unexpected
- dress for the weather conditions
- bring extra layers in case the weather changes
- change out of wet or sweaty clothes as soon as possible
- have non-alcoholic warm drinks
- make sure you're never too far away from help
Page last reviewed: 31 May 2017
Next review due: 31 May 2020