Hidradenitis Suppurativa: Pictures, Stages & Treatment
Hidradenitis suppurativa (HS) is a long-term inflammatory skin disease that causes recurrent painful lumps, abscesses and, over time, tunnels and scarring in areas where skin rubs together — the armpits, groin, buttocks and under the breasts. It is often mistaken for repeated boils for years before diagnosis, and earlier specialist treatment substantially changes the outcome.
Medically reviewed by Dr. Celina Kazumi Iwasa, MD · Last reviewed 2026-08-23
Quick answer
Hidradenitis suppurativa is a chronic inflammatory condition in which blocked hair follicles in skin folds produce recurrent painful nodules and abscesses that can discharge, join into tunnels and leave rope-like scars. It most often affects the armpits, groin, buttocks and under the breasts. Treatment ranges from topical and oral antibiotics and hormonal therapy to biologics and surgery, chosen by disease stage.
One free scan gives a first answer — the 3-month plan tracks how it changes over time.
What hidradenitis suppurativa looks like
HS begins with tender, deep lumps that feel like they sit under the skin rather than on it, often in the same few spots repeatedly. Over years, lesions can join into sinus tracts that discharge fluid, and healed areas leave firm, rope-like scarring. Severity is described in three Hurley stages.
Common locations
- Armpits (most common site)
- Groin, inner thighs and genital area
- Under the breasts and in the inframammary fold
- Buttocks and around the anus
- Waistline and nape of the neck
Typical signs
- Recurrent painful deep lumps in the same areas (Hurley stage I)
- Abscesses that discharge pus or blood-stained fluid, often with odour
- Sinus tracts — tunnels connecting lesions under the skin (stage II)
- Widespread interconnected tunnels with rope-like scarring (stage III)
- Blackhead-like double comedones in affected folds
On brown and Black skin
HS is more common and often more severe in Black patients. On deeper skin tones active inflammation may appear dark brown or violet, and post-inflammatory hyperpigmentation and keloid-type scarring are more prominent, so early treatment to prevent scarring matters even more.
Causes and triggers
HS is not caused by poor hygiene and it is not an infection that has been caught. It is an immune-mediated disease of the hair follicle: follicles in skin folds become blocked, rupture into surrounding tissue and trigger intense inflammation.
| Trigger | Why it matters |
|---|---|
| Genetics | Around a third of people have an affected family member; several gene variants affecting follicle biology are implicated. |
| Hormones | Onset is usually after puberty, and many women report flares before periods; the disease often quietens after the menopause. |
| Smoking | Strongly associated with both developing HS and with more severe disease; stopping is one of the highest-impact self-management steps. |
| Obesity and friction | Higher body weight increases skin-fold friction, sweating and inflammatory load; weight reduction improves severity for many people. |
| Mechanical irritation | Tight clothing, shaving and waxing in affected areas can precipitate lesions. |
| Associated conditions | HS is linked with inflammatory bowel disease, metabolic syndrome, polycystic ovary syndrome, arthritis and depression, which should be screened for. |
Conditions that look similar
HS is frequently misdiagnosed as recurrent boils. The clue is recurrence in the same fold-sites over months to years, with double comedones and scarring.
| Condition | How to tell it apart |
|---|---|
| Boils (furuncles) | Isolated staph infections that resolve with antibiotics and do not keep recurring in the same folds or form tunnels. |
| Folliculitis | Superficial pustules on hairs that clear within one to two weeks and leave no scarring. |
| Epidermoid cysts | Slow-growing, mobile cysts with a central punctum, painful only when inflamed, and not recurrent in crops. |
| Crohn's disease of the skin | Can produce perianal tunnels and ulcers; may coexist with HS and needs gastroenterology assessment. |
| Pilonidal sinus | Tunnel and discharge specifically in the natal cleft, often with visible hair, in a single site. |
Treatment options
Treatment is chosen by stage and aims to reduce flare frequency, control pain and prevent tunnels and scarring. HS responds best to early, sustained specialist care rather than repeated courses of antibiotics for individual abscesses.
Everyday management
Antiseptic washes such as chlorhexidine, loose breathable clothing, careful hair removal (laser rather than shaving where possible), warm compresses for painful lumps and effective pain relief.
Topical and oral antibiotics
Topical clindamycin for mild disease; oral tetracyclines for three months, or combined clindamycin and rifampicin for moderate disease — used for their anti-inflammatory effect as much as antibacterial.
Hormonal and metabolic therapy
Anti-androgen treatment such as spironolactone or combined oral contraception helps many women; metformin is used in some cases, particularly with insulin resistance.
Biologics
For moderate to severe HS, TNF-inhibitor and IL-17 inhibitor biologics are licensed and can substantially reduce flare frequency. These are prescribed and monitored by dermatology.
Procedures and surgery
Incision and drainage relieves an acute abscess but does not prevent recurrence. Deroofing of tunnels, laser treatment and wide excision of persistently affected areas offer longer-term control in stage II–III disease.
Smoking and weight support
Stopping smoking and, where relevant, weight reduction are the two lifestyle changes with the best evidence for reducing severity — worth clinical support rather than being left to willpower.
When to see a doctor
Anyone with recurrent painful lumps in the armpits, groin or under the breasts should ask for a dermatology referral — HS is commonly diagnosed years late, by which point scarring is established.
Red flags
- Two or more painful lumps in six months in the same fold area
- Lesions that discharge, tunnel or leave scars
- Fever, spreading redness or a rapidly enlarging painful area
- Pain limiting movement, work, sleep or intimacy
- Low mood, anxiety or isolation related to the condition — this warrants support alongside skin treatment
Frequently asked questions
What is hidradenitis suppurativa?
It is a chronic inflammatory disease of hair follicles in skin folds. Blocked follicles rupture beneath the skin and cause recurrent painful nodules and abscesses in the armpits, groin, buttocks and under the breasts, which over time can join into tunnels and leave rope-like scarring. It is not an infection you catch and is not caused by poor hygiene.
What are the stages of hidradenitis suppurativa?
Severity is usually described using the Hurley stages. Stage I is one or more isolated painful lumps without tunnels or scarring. Stage II is recurrent lesions with tunnels and scarring, separated by normal skin. Stage III is widespread interconnected tunnels and scarring across an entire area. Treatment intensity is matched to the stage.
Can hidradenitis suppurativa be cured?
There is no cure at present, but it can be controlled well. Early treatment with the right medication reduces flares and prevents tunnels and scarring, and surgery can remove persistently affected areas. Disease activity also tends to lessen after the menopause in many women.
Is hidradenitis suppurativa contagious?
No. HS cannot be passed to anyone else. Although lesions can become secondarily infected and discharge, the underlying disease is inflammatory, not infectious.
What makes hidradenitis suppurativa flare?
Common flare triggers include smoking, friction from tight clothing, shaving or waxing affected areas, heat and sweating, hormonal changes around periods, stress, and weight gain. Keeping a simple flare diary often reveals a personal pattern worth acting on.
Which doctor treats hidradenitis suppurativa?
A dermatologist leads treatment. General practice can start antibiotics and pain relief and make the referral, and plastic or general surgery becomes involved for deroofing or excision. Because HS is linked with inflammatory bowel disease, metabolic syndrome and depression, care often involves more than one team.
Not sure if it is hidradenitis suppurativa?
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This page is for general information and does not replace a medical consultation. If you are worried about a skin change, see a qualified clinician.