Psoriasis is a persistent, inflammatory skin condition. Some cases of psoriasis are so mild that people don’t know they have it. Alternatively, severe psoriasis may cover large areas of the body. Dermatologists can help even the most severe cases.
Psoriasis is not contagious, so it cannot be passed from one person to another. Psoriasis does, however, have a tendency to run in families, meaning it can be an inherited condition. Psoriasis
While the cause is unknown, research indicates that the immune system plays a key role. It is believed that the person’s immune system mistakenly activates T cells, a type of white blood cell. Once activated, the T cells trigger inflammation, which causes the skin to grow too rapidly. Normally, the skin replaces itself about every 30 days. When the process speeds up and the skin replaces itself in three to four days, psoriasis develops.
Psoriasis can be triggered by stress; an infection, such as strep throat; and by taking certain medicines, such as interferon and lithium. Cold, dry winter weather and lack of sunlight also can trigger psoriasis. Others see psoriasis flare 10 to 14 days after their skin is injured, such as by a cut, scratch, or severe sunburn.