Burns don't affect the skin uniformly, so a single injury can reach varying depths. Distinguishing a minor burn from a more serious burn involves determining the degree of damage to the tissues of the body. The following are four classifications of burns:
- First-degree burn. This minor burn affects only the outer layer of the skin (epidermis). It causes redness and pain and usually resolves with first-aid measures within several days to a week. Sunburn is a classic example.
- Second-degree burn. These burns affect both the epidermis and the second layer of skin (dermis), causing redness, pain and swelling. A second-degree burn often looks wet or moist. Blisters may develop and pain can be severe. Deep second-degree burns can cause scarring.
- Third-degree burn. Burns that reach into the fat layer beneath the dermis are called third-degree burns. The skin may appear stiff, waxy white, leathery or tan. Third-degree burns can destroy nerves, causing numbness.
- Fourth-degree burn. The most severe form of burn affects structures well beyond the skin, such as muscle and bones. The skin may appear blackened or charred. If nerve damage is substantial, you may feel no pain at all.
When to see a doctor
While minor burns can be cared for at home, call your doctor if you experience:
- Increased pain, swelling, redness or discharge in the burned area
- A burn that doesn't heal in several weeks
- New, unexplained symptoms
Seek emergency medical assistance for:
- Burns that cover the hands, feet, face, groin, buttocks or a major joint
- Chemical or electrical burns
- Third- or fourth-degree burns
- Difficulty breathing or burns to the airway