Seeing pus coming from any part of your body can be worrying, no matter the color. Leaking pus can be a symptom of hidradenitis suppurativa (HS), but it can also have many other causes.

Other types of wounds and infections can lead to pus. Keep reading to learn when you might see pus on your skin, both in general and with HS, and what different colors can tell you about whether a wound is infected.

Thanks! You've successfully submitted your vote.

Sign up to view the results!

Continue with Facebook

Continue with Google

Sign up with your email

By joining, you accept our Terms of Use, and acknowledge our collection, sharing, and use of your data in accordance with our Health Data and Privacy policies.

Already a Member? Log in

What Is Pus?

Pus is a fluid that can form in your body after it responds to a threat, such as an infection or an HS flare. In most cases, when your body detects something that could cause harm, it responds by sending white blood cells and other immune cells to attack the foreign invaders.

Your immune system then begins replacing the damaged cells and dead tissue with healthy cells and tissue. This leaves behind the damaged tissue and cells, which then blend with certain white blood cells called macrophages and neutrophils, forming pus. Simply put, pus is a sign that your body is trying to fight an infection in that area, and you should talk with a doctor or nurse, especially if the wound is painful, spreading, or not healing.

“Currently up with a flare-up. One of the areas has decided to burst and has a slowly oozing, almost mint-green color. Should I go to the hospital?”

— A myHSteam member

In many cases, your body will reabsorb pus that doesn’t drain from a wound, and you’ll never see it. But if the skin breaks over an area where pus forms, pus may ooze out and be visible.

When pus drains from a wound, it’s called purulent drainage.

Serous Drainage vs. Purulent Drainage

Pus isn’t the only type of fluid that may drain from a wound. Besides blood, you may see three other types of drainage from a wound. Some, but not all, may be a normal part of the healing process. The most common are serous drainage and purulent drainage.

• Purulent drainage — This thick pus comes out of a wound in the skin and may be a sign of infection.
• Serous drainage — This clear or yellow-tinged fluid is nearly the consistency of water. You may see it left on a bandage that covered a healing wound.
• Serosanguineous fluid — This is serous drainage mixed with small amounts of blood, making it a light pink color. You may see it on wound dressings after covering a new injury to the skin.

Serous and serosanguineous fluids are both considered a normal part of the wound healing process — unless the amount of drainage seems excessive.

If you’ve already been diagnosed with HS, you may be able to recognize HS discharge. In that case, follow the treatment plan your dermatologist recommended to manage it. If you haven’t been diagnosed with HS, talk with a doctor if you notice pus on your skin.

Identifying HS Drainage

HS lesions are caused by inflammation rather than infection, although secondary bacterial infections can follow. These infections develop in an area that’s already damaged or irritated. HS abscesses may look similar to an infection because of the open skin and pus drainage. Because treatment for an HS flare is different from treatment for an infection, and the two can happen at the same time, it’s important to know whether you have a flare, an infection, or both.

There’s no single test that can identify whether you’re experiencing HS versus an infection. If you’ve never been diagnosed with HS and you see pus on your skin, get medical help from your primary care provider. A dermatologist is the most appropriate person to identify HS and help you create a treatment plan tailored to meet your needs.

A healthcare professional can ask about your medical history to see if you’ve had itching, sore lumps or bumps, or other early HS symptoms. They might also take a sample of your wound drainage to see if it’s bacterial or not. In some cases, HS leakage doesn’t have bacteria in it.

What Pus Color Indicates an Infection?

If you don’t have HS, it’s important to see a doctor about any pus drainage, because it could be a sign of infection.

For people diagnosed with HS, it may be more challenging to identify an infection. For instance, pus accompanied by a foul smell may be a sign of a worsening infection in those without HS. But for people with HS, wound drainage with odor is often considered normal.

For that reason, it’s a good idea to know what different pus colors may mean. Though these won’t always be a sure sign of how your wound is progressing, they may be helpful as a guideline.

• White pus typically means the infection is starting to improve, but treatment may still be necessary.
• Yellow pus may be a sign of a bacterial infection, such as a staph infection (a common infection caused by Staphylococcus bacteria).
• Green pus may be a sign of a bacterial infection, often when the infection is more active or long-lasting.
• Pink or red pus usually means that blood is mixed with pus in the wound.
• Brown pus may be due to old blood mixing with pus, or it may be a sign of infection.

Always talk to a doctor about any concerning wound drainage. Bacterial infections usually require treatment with medications like antibiotics, and more serious infections may require a specialist to diagnose and treat.

“Currently up with a flare-up,” one myHSteam member wrote. “One of the five areas has decided to burst and has a slowly oozing, almost mint-green color. Should I go to the hospital?” Another member replied, “Always best to get it checked out.”

If you have HS and you’re concerned you may have an infected wound, call your doctor or go to a hospital.

Signs of Wound Infection With HS

In addition to pus changing color, other symptoms may mean that you’re experiencing an infection. Doctors often use the term “cellulitis” to describe bacterial skin infections.

"The important thing with cellulitis is to go to the doctor as soon as you notice something irregular.”

— A myHSteam member

“I was in the hospital for Thanksgiving because of cellulitis — I needed intravenous antibiotics. I was surprised how much it helped with the inflammation and pain,” one myHSteam member wrote.

Another member said, “I’ve been in the hospital several times with cellulitis. The last infection landed me in the ICU for two days. The important thing with cellulitis is to go to the doctor as soon as you notice something irregular.”

Cellulitis symptoms may include:

• Tender skin that’s sensitive, even to light friction
• Skin that feels warm to the touch
• Redness or discoloration and swelling that expand over time
• Discoloration and streaks that start at the affected area and move outward
• Fever

Any of these symptoms may be a sign of cellulitis and may require immediate medical attention and antibiotics. It’s important to start treatment as soon as possible to prevent the infection from spreading into your bloodstream. If cellulitis isn’t treated, it can lead to generalized sepsis, a life-threatening infection that affects your whole body. Always contact your doctor right away if you notice these symptoms.

Join the Conversation

On myHSteam, people share their experiences with HS, get advice, and find support from others who understand.

Have you ever had an infected wound? Let others know in the comments below.