Hidradenitis suppurativa (HS) is a chronic skin condition that causes painful lumps to form under the skin, usually in areas where skin rubs together — such as the armpits, groin, buttocks or under the breasts. These bumps can become inflamed, break open, and sometimes drain fluid or pus. Over time, repeated flare-ups can lead to scarring and tunnels (called sinus tracts) under the skin.

HS is not contagious and is often misunderstood as simple acne or an infection, but it’s a different condition that involves inflammation deep in the hair follicles. While there’s no cure yet, treatments can help manage symptoms, reduce flare-ups, and improve quality of life.