Hidradenitis Suppurativa (HS) is a long-term disease characterized by the occurrence of inflamed and swollen lumps and abscesses under the skin. These are typically painful and break open releasing malodorous fluid or pus. The areas most commonly affected are the underarms, under the breasts, and groin where there are folds in the skin.

The apparent starting point for HS is believed to be the hair follicle unit, the small pockets from which each hair grows. For reasons that are not totally clear, in HS the follicle closes then expands. As HS gets worse, pustules or pimples can develop, and they can develop into painful cysts, nodules. The follicle can then rupture resulting in an abscess with skin cells and pus spilling into the lower layer of the skin and make tunnels, tracts and eventually fibrotic scars.

The most common body areas affected by HS is the underarm, followed by the groin. The buttocks can also be affected by HS as well as just under the breasts. The distribution of HS lesions across the body usually differs in men and women.

Physicians often use the Hurley Staging System to describe HS with stage I being the least severe form of the disease and stage III being the most serious.

HS almost always occurs between puberty and age 40 and has been diagnosed as early as age 5. It is often described or regarded as a “rare” skin condition because it is not easily identified and because many patients never end up getting a diagnosis of HS even though they do have the condition. An estimated one quarter to one third of patients HS will have a family history of the condition.

The diagnosis of HS is made through a physical examination and taking a medical and family history. A biopsy or skin sample is sometimes taken to rule out other conditions. The diagnosis of HS is usually made by a dermatologist.

HS can have a significant negative impact on a person’s quality of life and many patients with HS avoid social interaction because they fear being embarrassed or stigmatized because of symptoms of the condition. It is not uncommon for patients with HS to have other medical conditions or be at risk of having other conditions such as obesity, metabolic syndrome, inflammatory bowel disease, arthritis, or depression.

Hidradenitis suppurativa Quick Facts

  • HS is not contagious
  • HS is not caused by poor hygiene
  • HS is more common in women than men
  • In women HS often improves after menopause
  • Smoking has been shown in association with HS
  • The average patients with HS will see 5 doctors before receiving a correct diagnosis.

Friction and Sweating:

Exercise and excessive sweating may trigger a flare. Clothing that you wear when you exercise may also contribute to the development of a flare by chafing against your skin, and aggravating HS. Wear more comfortable, loose-fitting clothing can prevent this by allowing the skin to breathe.


Some patients find that their HS is worse in hot, humid summer weather.


Clothing that does not breathe and is tight-fitting such as jeans might make your HS worse. It is preferable to wear clothing that fits loose and does not sit against the creases in your skin. Clothing that rubs against the skin can make your HS worse and promote a flare. Avoid wearing jeans and tight clothes when possible.

Weight Gain:

Some patients find that they have a flare of HS when they gain weight.  Weight gain aggravates HS flares in many ways including increasing friction. It is well-known that HS is associated with obesity, high blood pressure, diabetes, high cholesterol and overall higher cardiovascular risk. It has been shown that weight loss improves HS and helps HS management.


It has been shown that smoking is linked with HS and smoking is more common in patients with HS than in the general population. Smoking may trigger HS flares through different mechanisms.

Menstrual cycle in women:

Some women have observed a relationship between an HS flare and having their period. Some women have also found that their HS symptoms are worse when they are about to menstruate.

Changes in medication usage:

A flare of HS might result from a change in medication(s). Stopping medication might cause a flare of HS as well which is why adherence to the treatment plan is important to optimize outcomes. If a change in your medication results in a flare of HS, it is a good idea to consult with a doctor.

Stress management:

Stress may also produce a flare of your disease, so managing stress is important to prevent flares. Emotional distress may also be a trigger for your HS. HS may cause lots of stress and anxiety. Please do not hesitate to seek help to cope with the disease.

There is no cure for HS and flares often occur but the condition can be controlled with proper treatment. Treatment depends on the seriousness of the condition and patient preferences.

A number of lifestyle modifications can help control HS symptoms in the early stages. These include routine hygiene, weight loss for patients with high BMI, wearing loose-fitting clothing, smoking cessation, and use of ordinary soaps and antiseptic and antiperspirant agents.

Oral or topical medications such as antibiotics are commonly prescribed with less serious cases of HS. Adjunctive treatments include injections of the corticosteroid to short term control inflammation in nodules or small boils, therapies called anti-androgens that target the hormones in the body, other oral therapies called systemic immunosuppressants. More recently biologic therapies that regulate the immune system are being used to manage HS.

As HS has an inflammatory component, anti-inflammatory biologic therapies known as anti-tumor necrosis factor (anti-TNF) have been used to treat HS. These include adalimumab, infliximab and etanercept. Non-anti-TNF biologic agents that have been studied include anakinra and ustekinumab.

Surgery is also frequently used to manage HS lesions and is often necessary when tunnels form under the skin. Smaller lesions can often be removed locally. Individual lesions can also be treated by cutting and draining the lesion of any semi-solids and pus. Unfortunately. lesions usually recur with this approach.

If the HS is very advanced, surgery involving wide excision of the entire area that is affected is performed. Surgeons may have to graft skin from somewhere else on the body, for instance the thigh, and place it on the site where the original skin was removed, for instance the underarm.

Canadian Hidradenitis Suppurativa Foundation

A Guide to Hidradenitis Suppurativa: Living with HS