Hidradenitis suppurativa (HS) is a chronic skin condition characterized by painful lesions. HS lesions may heal and recur repeatedly, form scars, or burst and leak pus with a strong odor.¹ HS, also known as acne inversa, can negatively affect quality of life and be difficult to treat.²

Hidradenitis suppurativa is often mistaken for other skin conditions, including acne, boils, and sometimes genital herpes. Because HS can look like other common skin conditions, it’s best to see a dermatologist for a diagnosis.³

HS can occur at any age, but it often develops when people are in their early 20s. It’s more common in women than in men by a ratio of about 3 to 1.⁴ Early diagnosis and treatment can help manage HS symptoms, prevent progression, and avoid complications such as scarring.⁵

Unfortunately, there’s often a significant delay in diagnosis. One study found that the average time from the start of symptoms until a diagnosis of HS was 10 years.⁶ People with HS may experience low self-esteem and social isolation, as pain and visible effects on the skin can take a toll on relationships as well as on work or schooling.⁶

What Causes Hidradenitis Suppurativa?

Blocked hair follicles cause the symptoms of HS, but researchers don’t yet know what prompts that to happen and haven’t identified the exact cause of HS. Factors like genetics and hormones are believed to be involved in the development of HS.⁷

Where Does Hidradenitis Suppurativa Occur?

Skin contains two types of sweat glands. Eccrine sweat glands release fluid onto the surface of the skin, and apocrine sweat glands release fluid into the hair follicles.⁸ HS occurs on areas of the body containing apocrine sweat glands.⁷

Areas with apocrine sweat glands include⁷:

• The underarms
• The groin
• Under the breasts
• Between the buttocks

In some people, the nape of the neck and the waist can be affected by HS as well.¹

What Are the Symptoms of Hidradenitis Suppurativa?

The disease usually starts with one painful bump that remains for weeks or months. In some cases, the nodule resolves, but in others it becomes a painful abscess filled with pus.⁷

Symptoms of HS may include blackheads, as well as tender bumps or lesions that may grow larger. Hard, pea-sized lumps can also develop under the skin and persist for months.⁹

Swollen lumps associated with HS may rupture with a strong-smelling discharge, heal, and then return. These lesions sometimes turn into abscesses, which may leak pus and be hard to heal. Extensive tunnels under the skin, known as sinus tracts, may also form.^7,9

Sinus tracts can become linked under the skin’s surface, causing widespread inflammation.⁷ In severe cases, thick, painful scar tissue can form and may limit movement in affected areas.⁹

Some people with HS also experience itching, burning, and profuse sweating.⁵

HS can affect quality of life by causing psychological symptoms like depression and anxiety, as well as interpersonal issues such as problems with intimacy.¹⁰

“I’m having several flare-ups today, and I’m just extremely depressed — whenever this happens, all I do is sleep,” said one myHSteam member.

Another member wrote, “Stressed and wondering how I will ever hold a stable relationship when all I can think about are these scars and new flares on my body.”

Who Is at Risk of Hidradenitis Suppurativa?

HS usually begins in the years following puberty, though it’s possible to develop this condition into your 40s or 50s. HS is more than three times as common in women as in men.⁴ One review of 39 studies on people with HS determined that African Americans had the highest rates of HS.¹¹

Another study of 47,690 people with HS found that women, people who are African American or biracial, and people between ages 30 and 39 have the highest risks of HS.¹²

Genetics may play a role in the development of hidradenitis suppurativa, but not everyone with a family history of the condition will develop HS. In addition, some people who don’t have any relatives with HS may develop it.⁷

HS more commonly affects those who smoke cigarettes and people who have a higher body weight. Though not considered direct causes of HS, smoking and obesity are risk factors that may increase the chance of developing HS. Your doctor may advise you to quit smoking or may provide weight loss advice to help manage your condition.⁷

Common Misconceptions About HS

Many misconceptions about hidradenitis suppurativa contribute to the stigma around this painful and sometimes debilitating condition. Here are the facts.

What Are the Stages of HS?

Dermatologists use a system known as Hurley stages to describe cases of hidradenitis suppurativa from mild (stage 1) to severe (stage 3)¹³:

Stages of HS
	Hurley stage 1 (mild) — A single lesion or several abscesses without sinus tract formation or scarring
	Hurley stage 2 (moderate) — Recurring lesions in multiple areas with limited scarring and sinus tracts
	Hurley stage 3 (severe) — Multiple lesions, with more extensive sinus tract formations and scarring, possibly with HS abscesses that may cover the entire affected area

Some doctors also use a Sartorius score (also referred to as a hidradenitis suppurativa score or HSS) to describe HS symptoms. This score is based on which parts of the body are involved, the number and type of HS lesions, and the distance between lesions.¹⁴

Not all cases of hidradenitis suppurativa progress to more advanced stages, but some HS lesions can continue to worsen if not properly treated.⁹ Diagnosing and managing HS as early as possible is important to avoid progressing to a more severe stage.⁵

What Are the Treatment Options for HS?

Although there’s currently no permanent cure for hidradenitis suppurativa, treatments can control flare-ups, heal existing lesions, and keep your condition from progressing.³

Medications, which may include antibiotics, corticosteroids, hormonal treatments, and biologics, can improve symptoms for some people with HS. Some medications for HS are taken orally, while others are applied topically or injected.³

Your healthcare provider can help you understand your treatment options and how each type of medication works to treat HS. When discussing medications, be sure to ask about potential side effects or drug interactions.

For some people, medications aren’t enough to relieve their HS symptoms. In that case, surgical procedures may be helpful, and many can be done in-office by your dermatologist.³ Surgery sometimes successfully resolves HS symptoms, though lesions may recur in other areas of skin.¹⁵

Many people with HS experience anxiety, depression, and social isolation related to their symptoms. Psychological symptoms of HS may improve with talk therapy, cognitive behavioral therapy, or meditation. It can be helpful to engage with a support group in person or online, such as myHSteam.³

“Finding this community has made an amazing impact on my mental health,” one myHSteam member wrote. “It’s great to know I’m not alone in this battle — everyone is so supportive and has great advice.”

It’s just as important for people with HS and depression to seek treatment for their psychological symptoms as it is to treat their skin symptoms. If you’re feeling depressed, talk with your doctor about treatment and a potential referral to a mental health specialist.

Health Conditions Associated With Hidradenitis Suppurativa

People with HS may be more likely to have or develop certain other health conditions as well. These conditions include:

• Diabetes — This health condition is more likely to occur in people with HS.¹⁶
• Crohn’s disease and ulcerative colitis — Inflammatory bowel diseases have been associated with HS.¹⁶
• Obesity — This risk factor for HS can also exacerbate symptoms.¹⁶
• Heart disease — Cardiovascular conditions are sometimes present alongside HS.¹⁶
• Metabolic syndrome — This syndrome is a combination of high blood glucose, obesity, high cholesterol, and high blood pressure.¹⁶
• Rheumatoid arthritis and psoriatic arthritis — These types of arthritis often develop in people with HS.¹⁶
• Depression — Experiencing depression is common with many chronic health conditions, including HS.¹⁶
• Skin cancer and other skin diseases — Other skin conditions that cause open, noninfectious sores can also influence HS.¹⁶
• Spondyloarthritis — This type of arthritis, which typically causes low back pain, is associated with HS.^17,18