Psoriasis is a chronic, autoimmune disease that manifests in several forms, primary affecting the skin.  In many cases only one type of psoriasis will appear at a time.  In other cases several types may occur at the same time or after another form clears.

The most common form is plaque psoriasis.  Symptoms begin as small dry patches of skin, usually appearing on opposite sides of the body. These patches may or may not be noticeably inflamed. As the affect areas grow, the skin appears to grow in thicker, flaky layers. Some patches may be ring shaped. The edges are raised and the texture resembles snake scales. As more patches appear they often link together, forming larger areas.

While the symptoms caused by plaque psoriasis can be controlled, they may persist for long periods of time.  They often become worse when the weather gets cold, or during times of stress. It most often occurs on the elbows, knees and lower back. Treatments include coal tar or steroid based ointments and light therapy.

Guttate psoriasis often starts in children and young adults.  It appears as red spots on the torso, arms and legs. It usually begins suddenly and can incite a variety of symptoms that cause stress to the body and threaten overall health.  It can be brought on by upper respiratory infections, strep throat and skin trauma. Certain types of beta-blocking medications can worsen this condition.

Inverse psoriasis is characterized by smooth, shiny patches of inflamed skin. It usually occurs in body folds, such as under the arms, behind the knees, around the groin or under the breasts. Because of its location, flare-ups occur frequently due to the irritation of rubbing and sweating. Steroid creams are most commonly used, but can cause other skin issues if overused.

Other types of psoriasis spread indiscriminately across the entire body. An example of this is erythrodermic psoriasis. It may occur alongside pustular psoriasis.

Erythrodermic psoriasis is one of the more uncommon types of psoriasis.  It occurs in only one to two percent of the psoriatic population. Symptoms include severe itching, pain an a general imbalance of body chemistry.  Skin affected by erythrodermic psoriasis consistently looks as if it has been burned and body temperature fluctuates significantly with extreme weather conditions. While plaque psoriasis flakes off in small, scale-like patches, erythrodermic psoriasis causes larger sheets of skin to fall off all at once.  Those who suffer from this type of psoriasis are prone to different infections as well as pneumonia and congestive heart-failure, thus it is imperative to keep the condition under control.

Guttate Psoriasis:

Plaque Psoriasis: