What causes hidradenitis suppurativa?

The exact cause of hidradenitis suppurativa is unknown, but the lumps develop as a result of blocked hair follicles.

Smoking and obesity are both strongly associated with hidradenitis suppurativa, and if you’re obese and/or smoke it will make your symptoms worse.

Hidradenitis suppurativa usually starts around puberty, but it can occur at any age after puberty. This may suggest that sex hormones play a part. Many people with the condition also have acne and excessive hair growth (hirsutism).

In rare cases, hidradenitis suppurativa may be linked to Crohn’s disease, particularly if it develops around the groin area and the skin near the anus. Crohn’s disease is a long-term condition that causes the lining of the digestive system to become inflamed.

Hidradenitis suppurativa runs in families in about 1 in 3 cases. It’s not infectious and isn’t linked to poor hygiene.