Acne vulgaris is often referred to simply as acne. Comedones (blackheads or whiteheads), papules (small red bumps), pustules (pimples), nodules (large, painful lumps beneath the surface of the skin), and/or cysts (deep, painful, pus-filled lumps), which are a consequence of obstruction and inflammation of pilosebaceous units (sebaceous glands and the hair follicles they accompany), characterize acne vulgaris. The condition primarily manifests on the face and upper trunk, predominantly impacting adolescents.