What is Hidradenitis Suppurativa? HS Causes and Treatments Explained

Hidradenitis suppurativa (HS) can affect anyone, and it can be pretty unpleasant. Learn everything you need to know about causes and treatments for HS.

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Written by Nazar Hembara, PhD

Published 29 February 2024

Hidradenitis Suppurativa (HS) is a chronic skin condition, presenting as painful lumps under the skin. With HS affecting an estimated 1 to 4% of people worldwide, and causes still relatively unknown, understanding this condition is crucial for those affected, and clinical trials are essential for advancing treatment options. We discuss what is known about HS, covering causes, triggers, and treatments.

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What is hidradenitis suppurativa?

Hidradenitis suppurativa (HS), also called acne inversa, is a long-term skin condition characterized by the formation of painful, boil-like lumps beneath the skin. These lumps can cause significant discomfort and may rupture, resulting in abscesses that leak pus and fluid.

What causes hidradenitis suppurativa?

Hidradenitis suppurativa (HS) is considered an autoinflammatory condition, tied to systemic inflammation. The root cause of HS isn't fully understood, but it's believed to result from a mix of genetic predispositions and environmental triggers.

The process starts when hair follicles become blocked, leading to a buildup of bacteria and subsequent inflammation that can progress to HS. HS often first appears around puberty, indicating that hormonal changes may influence its development. There's also a significant genetic component, with up to 40% of sufferers reporting a family history of HS.

Additionally, its association with conditions like excessive hair growth and Crohn's disease, especially when symptoms occur near the groin or anus, points to an underlying link with systemic inflammation. Lifestyle factors, particularly smoking and being overweight, are known to worsen the condition's symptoms and its severity.

Who is more likely to get HS?

Hidradenitis suppurativa (HS) tends to occur more frequently in certain groups of people, suggesting various risk factors that might increase one's chances of developing the condition:

  • Gender and Genetics: HS is more commonly seen in women and those with a family history of the condition, hinting at genetic factors and possibly hormonal influences.
  • Lifestyle and Health Conditions: Being overweight, smoking, or having insulin resistance (also known as metabolic syndrome) can raise the risk of HS, underscoring the importance of lifestyle and metabolic health.
  • Ethnicity: Individuals of African descent and those with certain skin conditions like acne, psoriasis, and hirsutism have a higher likelihood of developing HS, indicating a role for genetic and dermatological factors.
  • Comorbidities: HS is associated with various other health issues, including inflammatory bowel disease (especially Crohn's disease), acne conglobata, pilonidal sinus, hypertension, diabetes, and polycystic ovary syndrome, suggesting it's part of a wider systemic issue affecting more than just the skin.

Hidradenitis suppurativa symptoms

The symptoms of hidradenitis suppurativa (HS) range significantly, from slight discomfort to intense pain and difficulties with movement. Initially, HS might show up as a single, painful lump beneath the skin that persists for weeks or months. As time goes on, more lumps can develop, particularly in areas with a lot of sweat and oil gland activity or where skin touches skin, like the armpits, groin, buttocks, and breasts.

Common symptoms include:

  • Blackheads: Small, indented spots with blackheads, usually found in pairs.
  • Lumps and abscesses: Red, painful lumps that grow, burst, and release pus and fluid, often causing itching and a bad smell.
  • Scarring and tunnels: Abscesses that heal slowly, recur, and cause significant scarring and channels beneath the skin.

How is HS diagnosed?

Diagnosing hidradenitis suppurativa (HS) is complex as there's no specific test for it. Diagnosis mainly relies on a clinical evaluation and patient's medical history. Here's a breakdown of the diagnostic process:

  • Clinical examination: A general practitioner (GP) examines the affected skin areas. Although HS isn't directly linked to common skin infection bacteria, a swab might be taken to help with diagnosis.
  • Medical history: The GP discusses your medical history and symptoms, focusing on recurrent painful lesions or abscesses more than twice in six months and any family history of HS.
  • Symptom assessment: Early stages of HS can be hard to distinguish from acne or pimples. Doctors look for lesions in typical areas (like armpits, groin, buttocks), nodules, sinus tracts, abscesses, and scarring.
  • Microbiology tests: Negative swab results or finding normal skin bacteria might indicate HS.

Physical signs important for diagnosis include:

  • Painful, red papules or nodules.
  • Abscesses and inflamed discharging lesions.
  • Dermal contractures and ropelike skin elevations.
  • Double-ended comedones.

Diagnosis also depends on identifying active disease, evidenced by primary lesions in specific areas and a history of recurrent lumps from a young age, or inactive disease, characterized by recurrent lumps without current primary lesions. This thorough approach enables healthcare professionals to diagnose HS effectively without a definitive test.

Hidradenitis suppurativa stages

HS progresses through stages, from mild symptoms to more severe forms, impacting both diagnosis and treatment strategies.

  • Early stages: Initial symptoms can resemble other skin conditions, starting with one or a few abscesses without scarring or sinus tracts, often mistaken for solitary sores.
  • First stage: This involves single or multiple isolated abscesses without scarring or sinus tracts.
  • Second stage: Characterized by recurrent abscesses with single or multiple lesions spaced apart. This stage sees the beginning of sinus tract and scar formation, indicating some localized scarring but limited sinus tract development.
  • Third stage: Marked by widespread involvement, with numerous interconnected sinus tracts and abscesses over a large area, resulting in extensive scarring and sinus tract involvement.

It’s also important to understand the severity classifications as this helps gauge the condition's impact:

  • Mild HS: Fewer than five inflammatory nodules or one abscess or draining fistula without more inflammatory nodules.
  • Moderate HS: Fewer than five inflammatory nodules or one abscess or draining fistula with one or more inflammatory nodules, or 2-5 abscesses or draining fistulas with fewer than 10 inflammatory nodules.
  • Severe HS: 2-5 abscesses or draining fistulas and 10 or more inflammatory nodules, significantly affecting health.
  • Very severe HS: More than five abscesses or draining fistulas, indicating the most difficult level of the disease to manage.

Recognising these stages and severity levels is vital for the effective management and treatment of HS.

Treatments for hidradenitis suppurativa

Managing hidradenitis suppurativa (HS) focuses on symptom relief and enhancing life quality, requiring ongoing or adaptable treatments due to its chronic nature. Common treatments include:

Medications and systemic treatments

When treating hidradenitis suppurativa (HS), the approach varies with the condition's severity, blending medications and systemic treatments for optimal management.

In mild cases, antibacterial skin washes or cleansers are used to reduce skin bacteria and fend off infections. Warm compresses can be applied to soothe boils, promoting drainage and easing discomfort.

As HS progresses to moderate or severe stages, treatment is likely to include topical medications to combat inflammation and prevent hair follicle plugging. Oral medications, such as antibiotics, fight infections and anti-inflammatory drugs help reduce swelling. Over-the-counter options like aspirin, ibuprofen, and naproxen are used to manage pain and inflammation.

Specific treatments may involve a short oral course of antibiotics for acute staphylococcal abscess, often with tetracyclines, or prolonged antibiotic courses combining clindamycin with rifampicin, tetracyclines with rifampicin, or a fluoroquinolone with metronidazole and rifampicin, usually for at least three months. In severe cases, intravenous Ertapenem may be considered.

Hormonal therapies, including oestrogens, anti-androgen therapy, and leuprolide acetate, are used to regulate hormones that may influence HS flare-ups. Immunomodulatory treatments such as systemic steroids for acute flares provide rapid relief from inflammation, with steroid-sparing agents like ciclosporin, methotrexate, and azathioprine used to manage symptoms with less reliance on steroids.

Adherence to your prescribed treatment plan is crucial, as your doctor will tailor this to your specific symptoms and severity.

Topical treatments

Topical treatments are used to reduce bacterial load and inflammation on the skin:

  • Triclosan/Benzoyl Peroxide Wash: This wash combines the antibacterial action of benzoyl peroxide with triclosan's antimicrobial effects, helping to lower skin bacteria and reduce inflammation.
  • Topical Clindamycin Phosphate 1% and Benzoyl Peroxide: Clindamycin, an antibiotic, reduces skin bacteria and inflammation. When used with benzoyl peroxide, it helps prevent hair follicle blockages and lessens the formation of new skin lesions.

Topical Antibiotics:

  • Fusidic Acid: Targets specific bacteria causing skin infections, beneficial for treating inflamed spots.
  • Dapsone: Offers anti-inflammatory and antibacterial benefits, useful in easing flare-up severity.
  • Metronidazole: Applied for its anti-inflammatory qualities, it assists in reducing redness and discomfort linked to HS.

Lifestyle changes and home remedies

To manage hidradenitis suppurativa (HS) effectively, incorporating specific lifestyle changes and home remedies can be beneficial:

  • Daily skin care: Opt for a non-soap cleanser and gently dry your skin. Avoid harsh scrubbing or squeezing lesions to prevent irritation.
  • Pain management: Warm compresses can help reduce swelling and pain. For additional pain relief and proper wound care, consult with healthcare professionals.
  • Healthy weight: Maintaining a healthy weight can help alleviate HS symptoms. Engage in activities suitable for your skin condition and seek professional advice on weight management.
  • Dietary adjustments: Consider reducing your intake of dairy, red meat, and foods with a high glycemic index. A dietitian can provide tailored advice on making these changes.
  • Quitting smoking: Smoking cessation can significantly reduce HS symptoms.
  • Loose clothing: Wear clothes that are loose-fitting to minimize skin irritation.
  • Avoiding heat and humidity: Opt for cooler and drier environments when possible to prevent exacerbation of symptoms.
  • Skin protection: Take measures to avoid skin injuries, which can trigger flare-ups.

Other treatments

For more severe or persistent cases of HS, other treatments may be required:

  • Incision and drainage: This procedure can offer immediate relief for acute abscesses by relieving pressure and pain.
  • Local excision: Targeted removal of persistent nodules, abscesses, and sinuses to reduce symptoms.
  • Radical excision: Involves the removal of entire affected areas to prevent recurrence of the condition.
  • Deroofing and curettage: This treatment is aimed at providing longer-term relief from persistent abscesses and sinuses.
  • Laser ablation (CO2): Utilizes laser technology to address nodules, abscesses, and sinuses effectively.
  • Laser/light hair removal: Can be beneficial by reducing hair that contributes to blockages and inflammation.

These approaches aim to alleviate symptoms, prevent recurrence, and enhance overall quality of life for individuals with HS.

Clinical trials for hidradenitis suppurativa

Currently, there are many clinical trials for hidradenitis suppurativa (HS), targeting different therapeutic areas. These trials are exploring a wide range of treatment options:

  • Cytokine inhibitors: These trials are investigating the role of cytokines, which are proteins involved in inflammation, to see if inhibiting them can reduce HS symptoms.
  • Non-biologic medications: This research is looking into various non-biologic treatment methods as potential options for HS.
  • Laser treatments: These studies are assessing how effective laser technology might be in alleviating HS symptoms.
  • Procedural treatments: Aimed at directly addressing the physical signs of HS, these treatments are under investigation for their efficacy.
  • Wound dressing techniques: Focused on improving healing and symptom management, these techniques are being tested for their potential benefits in HS care.

Interested in joining a clinical trial for Hidradenitis Suppurativa? Discover and match with trials suited to your needs and eligibility.

Begin your search today!

Hidradenitis suppurativa complications

Hidradenitis suppurativa (HS) can lead to severe complications, including deep infections known as abscesses and extensive scarring. This scarring can restrict movement, particularly in areas like the armpits or thighs.

The condition may also cause fistulas, abnormal passages within the body that can affect lymph nodes and lead to drainage issues. Additionally, HS is linked to arthritis, contributing to joint pain and swelling.

HS significantly impacts mental health, with sufferers facing potential depression and social isolation. Rarely, it can progress to more severe health issues like squamous cell carcinoma, anemia, cellulitis, and sepsis. It can damage the lymphatic system, leading to thick scars, pitted skin, or darker skin patches. In severe cases, fistulas may form between the skin and internal organs.

Effective management is crucial to minimize these risks and improve the quality of life for those with HS.

Can hidradenitis suppurativa be prevented?

Preventing hidradenitis suppurativa (HS) can be difficult due to its unclear causes, but as discussed earlier, there are some lifestyle changes that can be adopted to manage and reduce the risk of further flare ups:

Staying cool indoors during hot weather helps to limit sweating and skin irritation. Managing weight is also beneficial; reducing weight can decrease symptom severity since obesity is a significant risk factor. It's advisable to use unscented deodorants and skin care products to avoid irritating the skin. Quitting smoking is also important, as tobacco use can worsen HS symptoms. Wearing loose-fitting clothing can help minimize friction and skin irritation.


Hidradenitis suppurativa (HS) is a chronic skin condition that can have a significant impact on quality of life. Management of HS involves a combination of lifestyle adjustments, medical treatments, and possibly surgical interventions, depending on the severity of the condition. From skincare routines to medications and advanced therapies, treatment is customized to each patient's needs.

With ongoing research and clinical trials in individuals with moderate to severe HS, there is continuous progress towards better management and understanding of the condition, aiming to enhance the quality of life for those affected.


Is there a cure for HS?

While there is no cure for hidradenitis suppurativa (HS), treatments are available to help control the symptoms and manage the disease. This can significantly improve the quality of life for individuals affected by HS.

Is hidradenitis suppurativa contagious?

HS is not contagious and cannot be transmitted from person to person. The condition originates in the hair follicles and is exacerbated in areas where skin may touch or rub together, indicating its non-infectious nature.

What’s it like living with hidradenitis suppurativa?

Living with HS can be challenging due to the recurrent, painful abscesses that often lead to scarring. The visibility and chronic nature of these symptoms can make individuals feel self-conscious and can significantly impact mental health, highlighting the importance of supportive care and management strategies.

Is hidradenitis suppurativa an autoimmune disease?

The classification of HS has been debated; some researchers suggest it may be an autoimmune condition due to its association with systemic inflammation and immune system dysregulation. However, it's more accurately described as a systemic inflammatory disease, underscoring the complexity of its pathogenesis.Where do hidradenitis suppurativa boils form?

HS boils typically develop in areas of the body where skin rubs against skin, such as the armpits, groin, buttocks, under the breasts, and inner thighs. These locations are prone to friction and sweat, which can exacerbate the condition.

Is hidradenitis suppurativa due to poor hygiene?

HS is not caused by poor hygiene. The exact causes of HS are complex and not fully understood, but they are believed to involve genetic predisposition, immune system response, and possibly hormonal factors, rather than hygiene practices.

What types of skin growths does HS cause?

HS can lead to the formation of several types of skin growths, including nodules (firm lumps under the skin), abscesses (painful pockets of pus), and sinus tracts (channels that develop between abscesses and the skin surface). These growths can cause significant discomfort and require proper management to prevent worsening of the condition.

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