Acne Vulgaris - mild
Acne Vulgaris is the most common form of acne. Acne vulgaris lesions include blackheads, whiteheads, papules, pustules, nodules and cysts.
Mild to Moderate acne vulgaris consists of the following types of acne spots:
Whiteheads: Whiteheads result when a pore is completely blocked, trapping sebum (oil), bacteria, and dead skin cells, causing a white appearance on the surface. Whiteheads are normally quicker in life cycle than blackheads. You can view a diagram of a whitehead on the what is acne page. The Regimen provides a step-by-step program on how to treat whiteheads.
Blackheads: Blackheads result when a pore is only partially blocked, allowing some of the trapped sebum (oil), bacteria, and dead skin cells to slowly drain to the surface. The black color is not caused by dirt. Rather, it is the skin's own pigment, melanin, reacting with the oxygen in the air. A blackhead tends to be a stable structure, and can often take a long time to clear. You can view a diagram of a blackhead on the what is acne page. The Regimen provides a step-by-step program on how to treat blackheads.
Papules: Papules are inflamed, red, tender bumps with no head. Do not squeeze a papule. It will do no good, and may exacerbate scarring. The Regimen provides a step-by-step program on how to treat papules.
Pustules: A pustule is inflamed, and appears as a red circle with a white or yellow center. Pustules are your garden variety zit. Before you pop or squeeze such a lesion, be sure to read about how to pop a pimple. The Regimen provides a step-by-step program on how to treat pustules.
Acne Vulgaris - Severe
Severe acne vulgaris is characterized by nodules and cysts:
Nodules: As opposed to the lesions mentioned above, nodular acne consists of acne spots which are much larger, can be quite painful, and can sometimes last for months. Nodules are large, hard bumps under the skin's surface. Scarring is common. Unresolved nodules can sometimes leave an impaction behind, which can flare again and again. Absolutely do not attempt to squeeze such a lesion. You may cause severe trauma to the skin and the lesion may last for months longer than it normally would. Dermatologists often have ways of lessening swelling and preventing scarring, such as injecting the lesion with cortisone.
Cysts: An acne cyst can appear similar to a nodule, but is pus-filled, and is described as having a diameter of 5mm or more across. They can be painful. Again, scarring is common with cystic acne. Squeezing an acne cyst may cause a deeper infection and more painful inflammation which will last much longer than if you had left it alone. Dermatologists often have ways of lessening swelling and preventing scarring
Acne Rosacea
Acne Rosacea can look similar to the aforementioned acne vulgaris, and the two types of acne are sometimes confused for one another.
Rosacea affects millions of people, most of whom are over the age of 30. It appears as a red rash which is normally confined to the cheeks, nose, forehead and chin. The redness is often accompanied by bumps, pimples, and skin blemishes. Blood vessels may also become more visible on the skin. Blackheads are not part of rosacea. It is more prevalent in women, but often more severe when found in men. Left untreated, it can cause swelling of the nose and the growth of excess tissue, a condition called rhinophyma. Treatment is often different for rosacea than for acne, and it is important that you consult a dermatologist if you suspect you are experiencing rosacea.
Source : www.acne.org