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Boils under the breasts that keep scarring: when it's HS
Recurring boils under the breasts that drain or scar may be hidradenitis suppurativa (HS). Learn the signs, look-alikes, and which treatments can help.
Key takeaways
Recurring boils under the breasts may be a sign of HS. Painful lumps that repeatedly appear in the same areas, drain, or leave scars deserve evaluation by a dermatologist.
HS can be mistaken for ordinary boils or other skin conditions. A dermatologist can distinguish HS from infections, cysts, and rashes by evaluating your symptoms and medical history.
Friction, sweat, and hormonal changes may worsen HS symptoms. Simple adjustments, such as wearing less restrictive bras and keeping skin folds dry, may help reduce irritation.
Effective treatments are available. Depending on disease severity, dermatologists may recommend topical medications, oral treatments, biologics, or procedures.
Not every breast symptom is HS. New changes within the breast itself, including swelling, skin dimpling, or nipple changes, require prompt medical evaluation.
Painful lumps or boils under your breasts can be uncomfortable, especially when they keep coming back. While an occasional boil may result from a bacterial infection, recurring lumps in the same area may be a sign of hidradenitis suppurativa (HS), a chronic inflammatory skin condition.
HS commonly affects areas where skin rubs together, including beneath the breasts, in the armpits, and around the groin. Recognizing the pattern of symptoms can help you seek the right care and avoid delays in diagnosis.
Here's how to recognize possible HS under the breasts, what else may be causing your symptoms, and which treatments can help.
Why HS so often shows up in the breast fold
Hidradenitis suppurativa is a chronic inflammatory condition involving hair follicles. It causes painful, recurring lumps and abscesses that may drain, scar, or form tunnels beneath the skin.
HS often develops in areas where skin touches skin. Beneath the breasts, friction, warmth, and moisture can contribute to irritation and make symptoms more difficult to manage.
HS lesions may appear along the fold beneath one or both breasts, between the breasts, or alongside similar symptoms in the armpits or groin.
A study of patients with HS at a dermatology clinic in Brazil found breast involvement in 22 patients, with most of those patients experiencing lesions in the inframammary fold, the area directly beneath the breast. These findings describe one clinical population and should not be interpreted as a general prevalence estimate.
Importantly, HS is not caused by poor hygiene and is not contagious. It is a medical condition that requires appropriate diagnosis and treatment.
Signs that point to HS rather than an ordinary boil
An ordinary boil is typically caused by a bacterial infection involving a hair follicle. HS, by contrast, causes recurring inflammatory lesions that can progress over time.
Symptoms that may suggest HS include:
Lumps that return to the same spots
A lump that drains, seems to heal, then refills
Tunnels under the skin, called sinus tracts, that connect lumps and keep draining
Blackheads in pairs, known as double-ended blackheads
Rope-like or pitted scars along the fold
Lumps on both sides of the chest or in other folds
A single boil may resolve within a few weeks, while HS tends to follow a recurring pattern. If you're experiencing repeated boils beneath your breasts, particularly alongside scarring or drainage, a dermatologist can help determine whether HS is responsible.
On darker skin, inflammation may look purple, gray, or brown rather than red. Our guide to HS signs on darker skin shows how lumps and dark marks can appear.
Why HS is often treated as one boil at a time
When each boil under the breast is drained or treated with antibiotics on its own, the larger pattern is easy to miss.
A 2025 paper on diagnostic delay in BJGP Open, a survey of UK primary care, notes an average delay to diagnosis of 7–10 years. The same paper notes that, on average, a patient sees five clinicians and receives three incorrect diagnoses before HS is recognized. Boils, also called furuncles, and folliculitis, an inflamed hair follicle rash, are among the most common wrong diagnoses the BJGP Open paper lists.
Draining a lump eases pressure, yet the next one can still form. The inflammation sits deeper in the follicle, beyond what drainage reaches. For lumps elsewhere on the body, our guide explains why boils keep coming back and who to see.
Other causes of lumps and rashes under the breasts
Not every lump or rash beneath the breast is HS. Several conditions can cause similar symptoms, and distinguishing between them is important for choosing the right treatment.
Condition | What it looks and feels like | How deep | Pattern over time | Usual next step |
|---|---|---|---|---|
HS | Painful lumps that drain, with tunnels and rope-like scars | Deep in the skin, with tunnels underneath | Returns to the same spots, with new lumps over months | Dermatologist exam and a long-term treatment plan |
Ordinary boil | One red, painful, pus-filled bump | Deep in a single hair follicle | Usually heals within weeks and does not return | Warm compresses, and a doctor visit if it grows or you have a fever |
Yeast rash (candidal intertrigo) | Red, moist patches with scaly edges and small satellite spots | On the skin's surface | Flares with heat and moisture along the fold | Dermatologist exam, sometimes with a swab or skin scraping |
Epidermoid cyst | A smooth, rounded bump under the skin | Under the skin | Often stays in one place and can become inflamed | Dermatologist evaluation |
Breast abscess or mastitis | Redness, warmth, swelling, and pain in the breast | In the breast tissue | Often comes on quickly and is more common while breastfeeding | Prompt evaluation by a doctor |
Hormonal acne flare | Tender bumps that come and go | In the skin | May track with the menstrual cycle | Dermatologist evaluation to tell it apart from HS |
Intertrigo is inflammation that develops in skin folds, often associated with moisture and friction. As DermNet explains, yeast infections in these areas can cause moist, inflamed patches with scaling and smaller surrounding lesions.
Unlike a superficial rash, HS typically produces deeper inflammatory lumps and may lead to scarring or tunnels beneath the skin.
A dermatologist can evaluate your symptoms and determine whether additional testing is necessary. If a lump appears to involve breast tissue rather than the skin, further evaluation by an appropriate healthcare professional may be needed.
What makes breast-fold flares worse
HS is an inflammatory condition, but certain factors can worsen symptoms or contribute to flare-ups. Understanding your individual triggers can help you and your dermatologist develop a more effective management plan.
Bra friction, heat, and sweat
Underwires and tight bands can press and rub along the fold. The AAD offers dermatologist self-care advice noting that clothing that rubs can irritate HS skin and make it worse.
A 2020 International Journal of Women's Dermatology review gives women-specific care recommendations, including sports bras or camisoles with built-in wireless bras. These styles help offload pressure and friction from the fold.
The 2020 review and the AAD suggest small daily changes that can ease boils under the breasts during a flare:
Choose soft, absorbent fabrics such as cotton, rayon, or bamboo.
Tuck a moisture-wicking fabric, cut to fit, into the fold.
Dry the fold gently after bathing, using a hair dryer on the cool setting.
Stay cool, since the AAD notes that sweating and overheating tend to worsen HS.
Wash with benzoyl peroxide or zinc pyrithione, antimicrobial washes the AAD suggests.
Leave lumps unsqueezed, and use a warm compress to ease pain.
Skip waxing, since dermatologists advise people with HS never to wax.
Hormonal Changes and Menstrual Cycles
Many women notice flares in the days before their period, often in the same spots each month. That pattern can feel like cysts returning to the same place every cycle.
The same 2020 review in the International Journal of Women's Dermatology cites earlier research in which 43% of women reported HS worsening around their period. It lists oral contraceptives and spironolactone, a medicine that blocks some hormone effects, as options for premenstrual flares.
Tracking flares against your cycle helps your dermatologist decide whether hormonal therapy fits. A simple calendar note on each flare is enough to show the pattern.
Weight and smoking
The 2020 review in the International Journal of Women's Dermatology notes that larger breasts and skin folds add friction and a humid environment. The AAD notes that patients who quit smoking or lose extra weight can have fewer HS flare-ups.
These are levers that can ease symptoms over time. Your dermatologist can help you choose changes that fit your health and goals.
How a dermatologist confirms HS
No blood or skin test diagnoses HS, as our hidradenitis suppurativa condition guide explains. Diagnosis rests on the type of lump, its location, and its pattern over time.
The lumps that matter include nodules, tunnels, and scars. The location is usually skin folds, and the pattern is recurrence in the same areas.
A swab or culture can check for infection. A biopsy, the removal of a small skin sample for lab review, is sometimes used to rule out other conditions.
Your dermatologist also assigns a Hurley stage, a three-level scale of HS severity. Stage I means separate lumps without tunnels, stage II adds some tunnels and scars, and stage III means widespread, connected tunnels.
These details help your dermatologist see the full pattern of HS under the breasts:
Dated photos taken during flares
A flare timeline, including where you were in your cycle
A list of every area where lumps appear
Past drainages and antibiotics, and how well each worked
Any family history of HS or similar boils
Treatment that calms flares and limits new scars
HS is long-term, and treatment is built in steps. The goal is fewer flares, fewer new tunnels, and less pain.
Treatment aims to limit new scars along the fold. Scars that are already there can be treated too.
Medicines for active HS
For mild HS, dermatologists often start with antiseptic washes and topical clindamycin, an antibiotic applied to the skin. Oral antibiotics can help calm flares.
Hormonal therapy can help when flares follow your cycle. Options include estrogen-containing birth control pills and spironolactone.
Biologics are injected medicines that target specific immune signals behind HS inflammation. For moderate to severe HS, the AAD treatment guidance lists three FDA-approved biologics, adalimumab, bimekizumab, and secukinumab.
The AAD also notes that a corticosteroid injection can calm an early, painful lump that is not infected. It cannot treat tunnels under your skin.
Procedures for tunnels that keep draining
When tunnels keep draining, a dermatologist or surgeon may recommend a procedure. As our guide to recurring boils explains, deroofing opens the top of a tunnel so it can heal from the base. Excision is surgery that removes the affected skin.
Laser treatments are another option, and the AAD notes that laser hair reduction can reduce the number of nodules. Draining a lump relieves pressure, though the inflammation that forms the next one remains.
Procedures happen in person, while planning and follow-up visits can often be virtual.
Treating scars that are already there
Raised scars can respond to corticosteroid injections. Laser and other procedures are options chosen by scar type, as our page on treatment for scars and keloids describes.
In dermatologists' clinical practice, scar treatment usually works best once flares are controlled. That judgment shapes timing, so your dermatologist may treat active HS first.
Our guide to HS on darker skin explains that many dark areas after a flare are flat discoloration rather than scars. These marks can fade over time.
When a breast symptom needs a different evaluation
HS under the breasts lives in the skin of the fold. Changes in the breast itself need prompt evaluation by a doctor, who may order imaging.
The National Cancer Institute (NCI) lists signs of inflammatory breast cancer, including skin that is pink, reddish purple, or bruised. Its list also includes orange-peel dimpling, a rapid increase in breast size, and an inverted nipple.
The NCI notes that this cancer usually does not form a lump you can feel. Mastitis, a breast infection, can look similar, and a doctor can sort out the cause.
Contact your doctor promptly for evaluation if you notice any of these signs:
Skin that is pink, reddish purple, or bruised, or a breast that looks red and swollen
A feeling of heaviness, burning, or tenderness in the breast
Orange-peel dimpling or ridges on the breast skin
A rapid change in breast size
A newly inverted nipple
Swollen lymph nodes under the arm
A firm lump within the breast tissue also deserves a prompt visit with your doctor.
Seek same-day care for fever, spreading redness, or pain that worsens quickly.
Getting care for HS under the breasts
An HS specialist looks at the whole pattern and builds a plan for the long term. Specialized training gives dermatologists deep expertise in diagnosing and treating conditions of the skin, hair, and nails.
Tono's HS Center of Excellence covers diagnosis, biologic management, treatment escalation, longitudinal care, meaning follow-up over the long term, and coordination of procedural care.
The program is led by co-founder Dr. Mondana Ghias, Tono's Chief Medical Officer. She is a board-certified dermatologist and HS researcher with at least two dozen peer-reviewed publications.
Tono has cared for more than 20,000 patients across a 33-state clinical footprint. In many programs, appointments are available in two days or less.
Most insurance is accepted, and most plans need no referral. You can review insurance and referral details before booking.
Visits are virtual, with in-person care in Brooklyn and coordinated procedural care for cultures, biopsies, injections, and procedures. Tono can be your ongoing specialty home through flares and quiet stretches alike.
Frequently asked questions
Is HS under the breasts caused by poor hygiene?
No. HS is a chronic inflammatory condition involving hair follicles and is not caused by poor hygiene. It is also not contagious. Gentle cleansing may help reduce irritation, but washing alone will not treat the underlying disease.
Should I pop or drain a boil under my breast?
No. Squeezing or attempting to drain a boil yourself can worsen irritation and potentially spread infection. A warm compress may help relieve discomfort. If a lesion is particularly painful, large, or worsening, a healthcare professional can determine whether drainage or other treatment is needed.
Will HS scars under the breasts go away?
It depends on the type of mark or scar. Flat areas of discoloration may gradually fade, while raised or deeper scars are less likely to resolve completely without treatment. Controlling active HS can help prevent additional scarring.
Can HS under the breasts affect breastfeeding?
HS lesions beneath the breasts do not necessarily interfere with breastfeeding, but painful or actively draining lesions may create challenges depending on their location and severity. If you're pregnant, breastfeeding, or planning to breastfeed, discuss your symptoms and medications with your dermatologist and obstetric care team.
Can a dermatologist diagnose HS under the breast in a virtual visit?
In many cases, a dermatologist can evaluate possible HS through a virtual appointment using your medical history, symptom descriptions, and clear photographs. Some patients may need an in-person examination or additional testing to confirm the diagnosis or rule out other conditions.
Schedule an in-person or virtual appointment with a Tono Health specialist.
