A swollen sweat gland in the armpit, also known as a sweat gland abscess or hidradenitis suppurativa, occurs when one or more sweat glands in the armpit become inflamed and infected. This can cause a painful lump or nodule to form under the skin.
Sweat glands, also known as sudoriferous glands, are small tubular glands found in the skin that produce sweat. There are two types of sweat glands:
