Whiteheads are pimples that have a white head or tip to them. The whitehead forms on the face when a pore is completely blocked with sebum (oil), cellular material and P. acnes bacteria.
Blackheads
Blackheads are similar to whiteheads, except that the pimple is only partially blocked. The black material is not dirt as some believe, but melanin (pigment of the skin). Blackheads may last a long time on the face, because they take time to drain.
Pustules
Pustules are commonly referred to as zits. They have a white head in the middle and red enflamed skin surrounding it. Pustules are usually infected with bacteria and can also be yellow or green at the head.
Papules
Papules are skin lesions or pimples that do not have a head. They are simply red in color. Be careful with papules, as squeezing them can cause scarring.
Nodules
Nodules are usually referred to as severe forms of Acne Vulgaris. A nodule is a thick lesion that is usually underneath the skin's surface. They can cause scarring and be extremely uncomfortable. Many times nodules can take several months to heal. You should never try to pop a nodule. If you notice nodules under your skin, you should seek the advice and treatment from a dermatologist.
Cysts
Cysts are similar to a nodule, but are filled with infected pus. Cysts are usually 5mm or more in size and can sometimes be painful. You should never squeeze a cyst, since you can cause and internal infection. If you notice you have a cyst, you should consult with your dermatologist.
