Key takeaways

• A boil that returns to the same places, especially the armpits, groin, inner thighs, buttocks, or under the breasts, is worth a closer look.

• Many recurring boils are staph infections, and a lab test of the pus, called a culture, can identify the bacteria.

• When lumps drain, refill, and return despite antibiotics, a dermatologist can check for hidradenitis suppurativa (HS), a long-term inflammatory skin condition.

• HS is diagnosed through a skin exam and your history, so photos and a timeline of your flares help your doctor.

• Get same-day care for fever, spreading redness, or pain that is quickly getting worse.

Most boils heal once they drain. Recurring boils usually come from an infection that has not fully cleared, staph bacteria your body carries, or hidradenitis suppurativa (HS). HS is a long-term inflammatory condition of the hair follicles.

The next step depends on the cause. A doctor can test the fluid from an active boil to find the bacteria behind it. A dermatologist is the specialist who recognizes and treats HS.

Recurring boils follow a pattern, and that pattern is useful information. Where the lumps appear, how often they return, and how they respond to treatment are often the clearest clues to what is going on.

Why a boil keeps coming back after it drains

A boil, also called a furuncle, is a hair follicle that has become infected and filled with pus. MedlinePlus explains how ordinary boils form and notes that boils are most often caused by the bacterium Staphylococcus aureus.

Draining a boil relieves pressure, and a firm lump may linger for a while as the tissue heals. When the lump refills or returns, the cause usually follows one of two paths.

When the cause is bacteria

Sometimes a pocket of infection stays behind after drainage, and the boil fills again. Other times, staph bacteria carried in the nose or on the skin reseed the same area or start new boils nearby.

Some staph, including MRSA (methicillin-resistant Staphylococcus aureus, a strain that common antibiotics do not kill), does not respond to standard antibiotics. According to CDC guidance on MRSA, you cannot tell by looking at the skin whether an infection is MRSA.

A doctor can send pus to a lab for a culture, a test that identifies the bacteria and which antibiotics work against it. That result often explains why an earlier antibiotic did not help. For staph boils that keep coming back, doctors may also recommend steps to reduce the bacteria you carry on your skin and in your nose.

Everyday habits can help limit the spread of staph between people. The CDC recommends washing your hands, keeping wounds covered until they heal, and not sharing towels or razors.

When the cause is inflammation

Hidradenitis suppurativa is a long-term inflammatory condition that begins in the hair follicles. The NIH overview of HS describes it as chronic and noncontagious, with painful bumps, boils, and tunnels in and under the skin.

Because HS starts with inflammation deep in the skin, draining one lump does not stop the next from forming. Antibiotics may calm a flare, and the lumps can still return once the course ends.

HS often begins around puberty, affects about three women for every man, and can run in families. It does not spread to other people, and poor hygiene does not cause it. You can learn more about what hidradenitis suppurativa is and where it tends to appear.

Signs your boils may be hidradenitis suppurativa

HS has a recognizable pattern that builds over time. These are the signs people most often notice.

• Lumps return to the same areas, such as the armpits, groin, inner thighs, buttocks, or under the breasts.

• A lump drains, seems to heal, then fills again.

• Several lumps appear over months or years, rather than one isolated boil.

• Antibiotics help for a while, then the lumps come back.

• Tunnels form under the skin. These channels, called sinus tracts, connect lumps and may keep draining.

• Scars or thickened skin remain where lumps have healed.

• Flares started in the teens or twenties, or a relative has similar lumps.

HS most often affects the armpits and groin, and recurring boils on the inner thighs or buttocks can follow the same pattern. One Tono patient, Jovette Simmons, had boils drained in the emergency room and took antibiotics many times before learning she had HS. Her story is one patient's path to diagnosis, and she describes how "those areas always came back."

Ordinary boil or a pattern that suggests HS

The table below compares an ordinary boil with the pattern of recurring boils that often points to HS.

Only a clinician can tell the two apart with confidence. The pattern over time is what matters most.

Why HS is often mistaken for ordinary boils

Early HS can look like boils, pimples, or ingrown hairs. Each lump is often drained and treated on its own in urgent care or the emergency room.

There is no blood or lab test for HS. Doctors diagnose it from a skin exam and the history of where and how often the lumps appear. Mayo Clinic explains why drainage alone falls short in HS, since sores usually flare again and drainage is no longer considered an effective treatment.

Researchers reporting on an international survey of diagnostic delay estimated the average time from first symptoms to an HS diagnosis at about seven years. Other studies report different ranges.

That gap reflects how HS unfolds, one lump at a time. If you have had recurring boils for months or years, your own history is valuable. Noticing the pattern and bringing it to a dermatologist is what shortens the path.

Which doctor to see for boils that keep coming back

A single painful boil that needs draining today can be handled in urgent care or by a primary care doctor. They can drain it, culture it, check for diabetes and other conditions that affect healing, and refer you to dermatology.

For boils that keep coming back, especially in skin folds, see a dermatologist, ideally one experienced in HS. The NIH explains how doctors diagnose HS, often by examining the skin for boils in the locations typical of the disease.

What to bring to your appointment

HS is diagnosed from your history as much as from your skin on the day of the visit. Tono's guide to choosing an HS specialist explains what experience to look for. These details help your dermatologist see the full picture.

• Dated photos of lumps during flares, since lumps may be quiet on the day of your visit.

• A timeline of when the lumps started and how often they return.

• A list of every area affected, including areas that have healed.

• The drainage procedures, antibiotics, and other treatments you have tried, with how each one worked.

• Any family history of similar lumps.

• Your questions, such as "Could this be HS?" and "Should we culture this?"

What a dermatologist can offer

A dermatologist experienced in HS confirms the diagnosis, gauges how severe it is, and builds a long-term plan. In its guide to the treatment options dermatologists use, the American Academy of Dermatology (AAD) notes that HS can resemble acne, boils, or herpes. Dermatologists have the specialized training to tell these conditions apart.

A treatment plan can include topical and oral medicines. It can also include biologics, which are injected medicines that calm the inflammation driving HS, and several are FDA-approved for moderate to severe HS.

When tunnels or deeper lumps keep returning, a procedure may help. Deroofing opens the top of a tunnel so it can heal from the base. Excision is surgery that removes the affected skin.

HS cannot be cured, and a good plan is built for the long term. The AAD notes that treatment can reduce flares, heal wounds, relieve pain, and help keep the condition from worsening.

Cultures, biopsies, and procedures happen in person. A biopsy is a small skin sample examined in a lab. Ongoing follow-up and medication adjustments can often happen virtually, which makes long-term care easier to keep up.

When a boil needs urgent care

A single small boil can often be cared for at home. Get care the same day if you notice any of these signs.

• Fever or chills.

• Red streaks or redness spreading out from the boil.

• Pain or swelling that is quickly getting worse.

• A boil on your face or spine.

• A boil that keeps growing despite home care.

The CDC advises contacting a clinician if symptoms include a fever or do not improve within 48 hours. MedlinePlus also advises contacting a doctor if a boil does not heal with home treatment within a week or comes back after treatment.

Getting to the right specialist

Boils that keep coming back are a pattern worth naming. The right specialist can find the cause and build a plan for the condition behind the lumps.

Tono's HS specialty program covers diagnosis, biologic management, stepping up treatment when needed, long-term follow-up, and coordination of procedural care. Tono's co-founder and Chief Medical Officer is HS researcher Dr. Mondana Ghias, a board-certified dermatologist with more than two dozen peer-reviewed publications.

Tono has cared for more than 20,000 patients across a 33-state clinical footprint. Appointments are available in two days or less in many programs, which helps people with recurring boils reach a specialist sooner.

Visits happen virtually, with in-person care in Brooklyn and coordinated procedural care when you need it. Most insurance is accepted, and you can review insurance and referral details before you book.

HS is a long-term condition, and good care follows it over time. Tono is built to be an ongoing specialty home, with dermatologists who stay with your care through flares, quieter stretches, and changes in treatment.

When you are ready, you can schedule an appointment with a Tono Health specialist, in person or virtually.

Frequently asked questions

Why does my boil keep filling back up after it drains?

Usually, a pocket of pus or inflammation remains under the skin after drainage. With HS, the lump comes from inflammation in the hair follicle, so it can refill even after a thorough drainage.

Can recurring boils in the armpit be HS?

Yes, they can. The armpit is one of the most common places for HS. Lumps that return there over months or years are a good reason to see a dermatologist.

Will antibiotics cure HS?

No, antibiotics do not cure HS, though they can calm flares and are part of many treatment plans. Longer-term control usually comes from a plan that a dermatologist builds and adjusts over time.

Do I need a referral to see a dermatologist for recurring boils?

Often, no. Many insurance plans let you book a dermatologist directly, while some HMO plans require a primary care referral first. Tono does not require a referral for most plans.

Can a dermatologist diagnose HS in a virtual visit?

Often, yes. HS is diagnosed from how the skin looks and the history of flares, so clear photos help. If you need a culture, biopsy, or procedure, your dermatologist will arrange in-person care.