Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that causes painful lumps deep in the skin, usually in areas where the skin rubs together, such as the armpits, groin, buttocks, and breasts. It is also known as acne inversa. The lumps can fill with pus, break open, and drain blood and pus, leading to tunnels under the skin and scarring. HS can range from mild to severe, and the course of the disease is highly variable. The exact cause of HS is unknown, but it is thought to be due to a combination of genes, hormones, and the environment. It is more common in women than in men and is often associated with excess weight and smoking. HS is not contagious and is not caused by poor hygiene or sexually transmitted infections. There is no cure for HS, but treatments and lifestyle changes can bring some relief and cut down on flare-ups. Treatment options may include medication, procedures that can be performed in a dermatologists office, wound care, pain control, and self-care tips. Early diagnosis of HS is key to preventing it from worsening.