What are pressure ulcers?

Pressure ulcers are also known as bed sores and decubitus ulcers. These can range from closed to open wounds. They form most often after sitting or lying in one position too long. The immobility cuts off blood circulation over parts of your body, damaging surrounding tissues.

Pressure ulcers form predominantly on skin that covers bony areas of the body. Common places for bed sores to develop include:

If you develop a pressure ulcer, you may notice that they form in a series of four stages. These stages are based on how deep the sore is. In some severe cases, there are two kinds of pressure ulcers that cannot fit into one of the four stages:

  • suspected deep pressure injury
  • unstageable sores

Pressure ulcers can progress in four stages based on the level of tissue damage. These stages help doctors determine the best course of treatment for a speedy recovery. If caught very early and treated properly, these sores can heal in a matter of days.

Stage 1

The first stage is the mildest. It discolors the upper layer of your skin, commonly to a reddish color. In this stage, the wound has not yet opened, but the extent of the condition is deeper than just the top of the skin. The affected area may be sore to touch but has no surface breaks or tears. You may also experience mild burning or itching.

You may notice that the area is red and your skin does not turn pale when pressed firmly. This means there is an interruption in blood flow and that an ulcer is forming. The texture and temperature of this developing sore will likely also be different from the surrounding normal tissues.


The first step to treating an ulcer in this stage is to remove pressure from the area. Any added or excess pressure can cause the ulcer to break through the skin surface. If you are lying down, adjust your position or use pillows and blankets as extra padding.

It’s also important to keep the affected area clean and dry to reduce tissue damage. Stay well hydrated, and add foods high in calcium, protein, and iron to your diet. These foods help with skin health.

If treated early, developing ulcers in stage one can heal in about three days.

Stage 2

In the second stage, you’ll likely experience some pain from the ulcer. The sore area of your skin has broken through the top layer and some of the layer below. The break typically creates a shallow, open wound and you may or may not notice any drainage from the site.

A stage 2 ulcer may appear as a serum-filled (clear to yellowish fluid) blister that may or may not have burst. The surrounding areas of the skin may be swollen, sore, or red. This indicates some tissue death or damage.


Similar to treating stage 1 pressure ulcers, you should treat stage 2 sores by removing pressure from the wound. You must seek medical attention for proper treatment.

Your doctor will advise you to keep this area dry and clean. Clean the sore with water or a mild, sterile saltwater solution to dry out the wound. You may experience some pain or stinging.

Once you’ve cleaned the ulcer, discuss how to properly bandage it with your doctor. It’s also important to monitor the wound for any signs of infection including:

Healing from this stage can last anywhere from three days to three weeks.

Stage 3

Sores that have progressed to the third stage have broken completely through the top two layers of the skin and into the fatty tissue below. An ulcer in this stage may resemble a crater. It may also smell bad.

In this stage, it’s important to look for signs of infection including:


You must seek immediate medical treatment if you have a stage 3 pressure ulcer. These sores need special attention. Your doctor may prescribe antibiotic therapy and remove any dead tissue to promote healing and to prevent or treat infection.

If you are immobilized, your doctor may recommend a special mattress or bed to relieve pressure from the affected areas. Ulcers in this stage usually need at least one to four months to heal.

Stage 4

Stage 4 ulcers are the most serious. These sores extend below the subcutaneous fat into your deep tissues like muscle, tendons, and ligaments. In more severe cases, they can extend as far down as the cartilage or bone. There is a high risk of infection at this stage.

These sores can be extremely painful. You can expect to see drainage, dead skin tissue, muscles, and sometimes bone. Your skin may turn black, exhibit common signs of infection, and you may notice a dark, hard substance known as eschar (hardened dead wound tissue) in the sore.


People with stage 4 pressure ulcers need to be taken to the hospital immediately. Your doctor will likely recommend surgery. Recovery for this ulcer can take anywhere from three months to two years to completely heal.

Additional types

In addition to the four main stages of pressure ulcer formation, there are two other categories: suspected deep tissue injury and unstageable pressure ulcers.

Ulcers that form from suspected deep tissue injury can be difficult to diagnose. On the surface, it may resemble a stage 1 or 2 sore. Underneath the discolored surface, this ulcer could be as deep as a stage 3 or stage 4 wound. This pressure ulcer may also form as a blood blister, or be covered with eschar.

Unstageable pressure ulcers are also hard to diagnose because the bottom of the sore is covered by slough or eschar. Your doctor can only determine how deep the wound is after clearing it out.

The ulcer may be yellow, green, brown, or black from slough or eschar. If there is extensive tissue damage, it will need to be surgically removed. However, in certain areas of the body, if the covering is dry and stable, it shouldn’t be touched. This dry eschar is the body’s natural layer of protection.

Pressure ulcers are wounds that develop once a pressure injury causes blood circulation to be cut off from particular areas of the body. Damage to affected tissues can be categorized into four stages.

These sores are more common among the elderly, people with limited mobility, and people who are bedridden from illness or other conditions. Though treatable, pressure ulcers can cause a number of complications such as infection and need for amputation. They can take years to heal if not diagnosed and treated early.

If you begin experiencing symptoms with skin changes or pain from immobilization, seek immediate medical attention.