Health Topic

Hidradenitis Suppurativa

Hidradenitis suppurativa (HS), or acne inversa, is a chronic skin disease. It causes painful bumps in your armpits and groin. Learn about treatment.

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Also called: Acne inversa · Suppurative hidradenitis

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic skin disease. Another name for it is acne inversa. It causes painful, boil-like lumps that form under the skin. It often affects areas where the skin rubs together, such as your armpits and groin. The lumps become inflamed and painful. They often break open, causing abscesses that drain fluid and pus. As the abscesses heal, they can cause scarring of the skin.

The lumps in HS form because of blockages of the hair follicles. The blocked hair follicles trap bacteria, which leads to inflammation and rupture. In most cases, the cause of the blockages is unknown. Genetics, environment, and hormonal factors may play a role. Some cases of HS are caused by changes in certain genes.

HS is not caused by bad hygiene, and it cannot be spread to others.

HS usually starts after puberty, usually in the teens or twenties. It is more common in:

  • Women
  • People who are Black
  • People with a family history of HS
  • People who are overweight or have obesity
  • People who smoke

The symptoms of HS include:

  • Small pitted areas of skin containing blackheads
  • Painful, red, lumps that get bigger and break open. This causes abscesses that drain fluid and pus. They may itch and have an unpleasant odor.
  • The abscesses heal very slowly, recur over time, and can lead to scarring and tunnels under the skin.

HS can be mild, moderate, or severe:

  • In mild HS, there are only one or a few lumps in one area of the skin. A mild case will often get worse, becoming a moderate disease.
  • Moderate HS includes recurrences of the lumps that get bigger and break open. The lumps form in more than one area of the body.
  • With severe HS, there are widespread lumps, scarring, and chronic pain that may make it hard to move.

Because of the difficulty of dealing with the disease, people with HS are at risk for depression and anxiety.

There is no specific test for HS. It can be hard to diagnose in the early stages because it can look like pimples or acne. To make a diagnosis, your health care provider:

  • Will ask about your medical history and your symptoms
  • Will look at the lumps on your skin
  • May take a sample of the skin or pus (if there is any) and send it to a lab to be tested

Your provider may refer you to a dermatologist (skin doctor) to get a diagnosis or treatment.

There is no cure for HS. Treatments focus on the symptoms, but they are not always effective for everyone. The treatments depend on how severe the disease is and may include:

  • Medicines, including steroids, antibiotics, pain relievers, and medicines that flight inflammation. In mild cases, the medicines may be topical (applied to your skin). Otherwise, the medicines may be injected or taken orally (by mouth).
  • Procedures or surgery to remove the lumps and scars or make the sores go away.

It may also help if you can avoid things that can irritate your skin, by:

  • Wearing loose-fitting clothing
  • Staying at a healthy weight
  • Quitting smoking
  • Avoiding heat and humidity
  • Being careful not to injure your skin

It sits within Skin, Hair and Nails.

The lead U.S. institute for this subject is the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Hidradenitis Suppurativa

274 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Genetics

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Hidradenitis Suppurativa. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Hidradenitis Suppurativa, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.