Comedonal acne occurs when a type of oil is produced in the skin that allows the surface of the hair follicle to become clogged with keratin, resulting in blemishes known as blackheads and whiteheads.
Blackheads, also known as open comedones, are yellowish or dark in color, and appear as small plugs in the pores. They become darker as the keratin oxidizes in the air.
Whiteheads are closed comedones that appear as small bumps on the skin with a small white central area. These occur deeper in the follicle than open comedones.
When the pores become clogged, an overgrowth of bacteria can occur, leading to inflammation and skin eruptions, commonly known as zits or pimples. Large acne (pimples or zits) can be tender. This condition not only causes physical discomfort and damage, but it can also have a big emotional and social impact on your life. If you are feeling embarrassed and anxious about your appearance, these emotional side effects can lead to mood changes, depression, social withdrawal and poor performance in school or at work.