Complications from burns and scalds can include:

• going into shock
• heat exhaustion and heatstroke
• infection
• scarring

Shock

After a serious injury, it is possible to go into shock. Shock is a life-threatening condition that occurs when there is an insufficient supply of oxygen to the body. It's possible to go into shock after a serious burn.

Signs and symptoms of shock include:

• a pale face
• cold or clammy skin
• a rapid pulse
• fast, shallow breathing
• yawning
• unconsciousness

Dial 999 and ask for an ambulance if you think that someone who has been seriously injured is going into shock.

While you wait for the ambulance:

• lay the person down (if their injuries allow it) and raise and support their legs
• use a coat or blanket to keep them warm, but do not cover their face or the burnt area
• do not give them anything to eat or drink

Heat exhaustion and heatstroke

Heat exhaustion and heatstroke are two heat-related health conditions that happen when the temperature inside your body rises to 37-40C (98.6-104F) or above.

Both heat exhaustion and heatstroke can be very serious. They are often caused by being exposed to too much sunlight or heat. Similarly, if someone is sunburnt, they may be at risk of developing heat exhaustion or heatstroke.

Symptoms of heat exhaustion and heatstroke include:

• extreme tiredness and lack of energy
• dizziness or fainting
• feeling sick or vomiting
• rapid pulse
• headache
• muscle pain
• irritability
• confusion

If a person with heat exhaustion is taken quickly to a cool place, given water to drink and has their clothing loosened, they should start to feel better within half an hour. If they don’t, they could develop heatstroke. This is a medical emergency and you’ll need to call 999 for an ambulance.

Read more about what to do if someone has heat exhaustion or heatstroke. 

Infection

Wounds can become infected if bacteria get into them. If your burn or scald has a blister that has burst, it may become infected if it is not kept clean. Seek medical attention for any burn that causes a blister.

Your wound may be infected if:

• it is uncomfortable, painful or smelly
• you have a high temperature of 38C (100.4F) or higher 
• you have signs of cellulitis, a bacterial infection that causes redness and swelling of the skin

Seek immediate medical attention if you think your burn has become infected. An infection can usually be treated with antibiotics and painkilling medication, if necessary.

In rare cases, an infected burn can cause blood poisoning (sepsis) or toxic shock syndrome (TSS). These are serious conditions that can be fatal if not treated. Signs of sepsis and toxic shock syndrome include a high temperature, dizziness and vomiting.

Scarring

A scar is a patch or line of tissue that remains after a wound has healed. Most minor burns only leave minimal scarring. You can try to reduce the risk of scarring after the wound has healed by:

• applying an emollient, such as aqueous cream or emulsifying ointment, two or three times a day
• using sunscreen with a high sun protection factor (SPF) to protect the area from the sun when you are outside