When it comes to burns, you’ve likely heard that third-degree burns are the worst. However, the degrees of burns can actually go higher.

Though not commonly mentioned, burn classification includes fourth-degree burns, as well as fifth and sixth. Fourth-degree burns aren’t as well known is because they aren’t as common as burns of lower degrees.

Fourth-degree burns can have serious consequences. Let’s take a closer look at how you can identify these types of severe burns and what steps you can take to treat them.

Burns are classified based on the extent of damage they cause to the body.

Degree of burn What it
looks like
Damage Long-term outlook
First (superficial) red and dry, but without blisters (such as mild sunburn) top layer of skin (epidermis) temporary skin color changes
Second red, swollen, and blistered skin top and middle layers of skin (dermis) may cause an increase in skin thickness
Third white and charred-looking epidermis, dermis, and subcutaneous (fat) tissues extensive skin damage, including thicker skin and scars as it heals
Fourth charred skin with possible exposed bone skin, tendons, nerves, and possibly muscles may cause permanent damage to affected area, requiring amputations
Fifth charred, white skin and exposed bone skin, tendons, muscles, and bones permanent body damage, amputation, and organ damage possible
Sixth loss of skin with exposed bone extends to the bones same as fifth-degree burns, but with possible fatalities

Fourth-degree burns are primarily caused by flames and chemicals. Some of the possibilities include:

  • a hot stove or oven
  • hot irons
  • open flames, such as fireplaces or campfires
  • injuries from a building fire
  • chemicals

These can also cause lesser-degree burns. What makes a burn fourth-degree, however, is the extent of the damage to your body.

Third-degree burns can affect deep layers of your skin, including fatty tissues. Fourth-degree burns also go much deeper, affecting your muscle tissues, tendons, and nerves.

With a fourth-degree burn, you’ll first notice that the affected area has a charred-looking appearance. It may even be white in color. You might see exposed bone and muscle tissue.

Unlike first- or second-degree burns, fourth-degree burns aren’t painful. This is because the damage extends to the nerves, which are responsible for sending pain signals to your brain.

Such nerve damage makes this burn level even more dangerous — just because you can’t feel the pain doesn’t mean that the burn isn’t serious.

A fourth-degree burn is considered a medical emergency. An ER doctor at a hospital’s burn unit will diagnose your burn and treat you accordingly.

If you or a loved one has this type of a severe burn, call 911 right away. The sooner you seek treatment, the less you’re at risk of complications. Emergency responders will take you to a hospital with a burn unit in its emergency room.

The precise treatment for your fourth-degree burn will depend on the extent of the damage to your body, as well as your overall health. While waiting for an ambulance to arrive, you can help a burn victim by:

  • raising the injured body part above the heart, if possible
  • covering the affected area with a loose bandage or cloth
  • placing a light sheet or blanket over them, especially if they appear cold from reduced blood pressure
  • flushing the area with water (for chemical burns only)

The actions you don’t take are perhaps just as important as the ones you do take. As you wait for emergency medical attention, make sure you:

  • don’t apply ice
  • don’t apply creams or ointments to the burns
  • don’t remove clothing that may be stuck to the burn
  • don’t pick at skin or peel away any blisters

Once you get to the burn unit, the doctor may take a variety of approaches to treatment. They’ll first clean the burn and remove any dead tissues.

Much of your treatment depends on how much of your bones, muscles, and nerves are affected, as well as the location of the burn itself. Your doctor might do one or more of the following:

  • prescribe pain medications
  • apply antibiotic ointments in the case of an infection
  • order a tetanus shot, if you haven’t had one in the last 10 years
  • use intravenous fluids to help prevent dehydration and low body temperature

At this time, you’re also at a high risk of experiencing shock. This is due to the large inflammatory response from your body as it contends with the changes the burn has suddenly made to the affected area. Your major organs can also become susceptible to inflammation, including your heart.

As the burn heals, your doctor will be able to determine the overall extent of the damage to your body. Cosmetic reconstruction methods, such as skin grafting, may be necessary if your skin doesn’t generate any new tissues.

You may also need to consider other treatments, such as physical therapy, if you’ve lost feeling in the area. Further medical treatments may be necessary for damaged joints and lost muscles.

Fourth-degree burns are serious, as these affect more than just your skin. It’s important to remember that because of potential nerve damage, severe burns may not necessarily be painful.

The longer you wait to seek treatment, the higher your risk of potential life-threatening complications, such as loss of circulation and organ damage. Amputations are also possible.

However, the good news is that medical science has come a long way in burn treatments.

According to the National Institute of General Medical Sciences, even people with 90 percent of their bodies covered in burns may survive, though permanent damage is to be expected.

If you think your loved one has a severe burn, you can help them by calling 911 or your local emergency services right away.