Finding a hard lump under your skin after a boil drains can be worrying. Boils are common and usually not serious, but a lingering lump can cause stress.

In this article, we’ll explain how to manage a boil that doesn’t seem to be healing, how to care for your skin after a boil, and when to see a healthcare professional.

How Boils Form and Heal

To understand why a hard lump might stay after a boil drains, it helps to know what boils are.

Boils are bumps on your skin that are caused by bacterial infections in hair follicles. They contain pus and can be quite painful. They look like large pimples but form deeper under your skin. Boils (also called furuncles) are usually shiny and red, with a white or yellow center.

As the infection grows, the bacteria under your skin kills skin cells and creates a pocket of pus called a skin abscess. When the boil drains, the pus is released, but sometimes a hard lump remains.

Managing a Boil at Home

Some boils heal on their own, but others need care, whether with over-the-counter products or home treatments. You can apply a clean, damp washcloth or warm compress to the affected area multiple times a day. This helps reduce pain and encourages drainage. You can keep using this method even after the boil drains.

Make sure you wash your hands before and after putting dressings on your boil to avoid spreading bacteria. Don’t share towels or items that have touched your boil, and throw away any used bandages in a sealed bag.

In some cases, a doctor may need to drain a boil to help it heal. However, you should never try to pop, squeeze, or cut a boil open yourself. Doing this can spread bacteria from the boil to other parts of your body and increase the risk of a skin infection.

Even if you care for your boil properly with home remedies, you might notice a hard lump under the skin after a boil drains. This could mean it hasn’t healed completely. If this happens, it’s best to see a doctor.

When To Call a Doctor About a Boil

Just because a boil drains doesn’t mean it’s fully healed. If you have a boil that keeps coming back or won’t heal, this could signal an ongoing infection or another underlying condition. Contact a healthcare professional if a hard lump remains under your skin after your boil has finished draining.

You should also get medical advice right away if you notice any of the following:

• The boil becomes more painful.
• You develop a fever.
• The boil doesn’t heal after a week.
• The boil is on your face.
• The boil is on your back, especially over the spine.
• The boil returns after draining.

A medical professional can evaluate whether you need antibiotics or other medical treatment to clear the infection. They can also help you avoid the spread of infection and evaluate you for other skin conditions.

For example, hidradenitis suppurativa (HS) is a condition that causes painful lumps to form under the skin, and HS may be confused with nonhealing boils. HS lesions can rupture and leak pus, similar to boils. A dermatologist can help you figure out whether you have HS or if another issue is causing your symptoms.

If you’re concerned about a hard lump under your skin after a boil drains, your doctor is the best person to help. Don’t hesitate to reach out to them if you’re concerned.

Talk With Others Who Understand

At myHSteam, you’ll find the social network for people with hidradenitis suppurativa and their loved ones. On myHSteam, more than 46,000 members come together to ask questions, give advice, and share their stories with others who understand life with hidradenitis suppurativa.

Have you experienced any large boils or painful lumps that didn’t heal properly? Did you see a dermatologist? Which treatments or home remedies worked for you? Share your experience in the comments below, or start a conversation by posting on your Activities page.