Psoriasis is known as the waxing and waning condition, and it can and does go away. Psoriasis is probably one of the longest known illnesses of humans and simultaneously one of the most misjudged and misunderstood. Psoriasis affects both sexes equally and can occur at any age, although it most commonly appears for the first time between the ages of 15 and 25 years. Psoriasis does get worse over time but it is not possible to predict who will go on to develop extensive psoriasis or those in whom the disease may appear to vanish.

Psoriasis is not an infection and therefore is not contagious. Psoriasis flare-ups can last for weeks or months. Psoriasis is fundamentally an inflammatory skin condition with reactive abnormal epidermal differentiation and hyperproliferation.

Psoriasis can cause as little as a single dimple on one of your finger or toe nails, or affectas much as the majority of your skin surface, your joints, and your eyes.

Ultraviolet B (UVB) phototherapy--UVB is light with a short wavelength that is absorbed in the skin's epidermis. Ultraviolet light treatment is frequently combined with topical (coal tar, calcipotriol) or systemic treatment (retinoids) as there is a synergy in their combination. Ultraviolet light treatments include the milder UVB, or for the more severe or extensive psoriasis (psoralen and ultraviolet A [PUVA] therapy.