Psoriasis is fairly common skin disorder that may affect people of any age, though it usually begins between ages 15 and 35. It can appear both suddenly or slowly, and in many cases, it goes away only to repeatedly flare up again as a lifelong condition. Little is known about what causes psoriasis. In psoriasis there is an overproduction of skin cells which rise too quickly to the outer layer and build up as dead cells on the skin's surface.

Melanoma is a serious type of skin cancer associated with the melanocytes, the cells that product the pigment that gives your skin its color. Because melanoma is usually the result of excessive exposure to the UV radiation, it most often develops in areas that have had exposure to the sun, such as your back, legs, arms and face. However, it can also occur in areas that don't receive much sun exposure, such as the genitalia, eyelids and soles of your feet or palms of your hands, particularly in the case of people with darker skin.

Dermatitis is an inflammation of the skin that can results from direct contact with certain substances, such as soap, cosmetics, jewelry or weeds, including poison ivy or poison oak. Symptoms of contact dermatitis can include red, itchy rash, dry patches resembling burns, pain or tenderness, and in some severe cases, blisters and draining fluid. Contact dermatitis isn't contagious or life threatening, but it can be very uncomfortable.