There have been recorded cases of psoriasis since 35 A.D. and there is even some evidence that it existed before that time. Despite the longevity of its existence there is still very little known about what actually causes psoriasis. Scientist do know more than previously, but still have far to go regarding fully understanding what causes the inflammatory skin condition. The research so far seems to support that the possible causes of psoriasis are genetic, immune system, and also environmental. It is known through the reaction of kidney-transplant recipients who had psoriasis and experienced clearing of the condition after immunosuppressive medication; that the immune system is somehow involved in the occurrence of psoriasis. They believe that psoriasis may develop due to faulty signals in the body's immune system. The immune system over-reacts and results in an accelerated skin cell growth that appears to the naked eye as psoriasis. This normal acceleration process of skin cell growth typically takes 28 to 30 day and shortens it to only 3 to 6 days for the new cells to mature and rise to the surface. The rapidly growing cells than pile up on the skin instead of being shed. This skin cell buildup causes the lesions that are visible on the skin's surface.
Researchers believe that the reason some family members develop psoriasis and others do not is because of something called, "triggers". A trigger is necessary before the skin condition will occur. Common triggers for psoriasis are: the presence of sunburn, skin injury, strep infection, stress and also certain medications such as anti-malarial drugs, beta-blockers and lithium. A flare-up of psoriasis or the very first occurrence of psoriasis can present itself shortly after one of these medications have been taken by an individual who has a family history of psoriasis.
Research for answers to the cause and behavior of psoriasis is an ongoing thing. Future treatment plans and the relief of millions of psoriasis sufferers is dependant on this research.
Individuals who are predisposed because of genetics may also develop psoriasis as the result of an environmental trigger such as the weather. Exposure to direct sunlight during the warmer weather months can be a trigger for psoriasis flare-ups so can the cold temperatures of winter and the harsh winds that can accompany winter coldness.
Stress can trigger psoriasis although scientists are not certain how exactly it does it. Individuals who are considered to be in the category of being a "high level worrier were twice as likely to experience a flare-up and to not respond to treatment as compared to an individual who were considered to be a low worrier.
Other things that are thought to be triggers of psoriasis are bacterial or viral infections and streptococcal infections that cause tonsillitis or strep throat, tooth abscess, cellulites and also impetigo. It is thought that the HIV virus does not increase the occurrence of psoriasis; however it does increase the severity of it. Low levels of calcium in the body can trigger psoriasis. Certain medications can either cause a flare-up or cause an active case of psoriasis to become worse. These drugs are: captopril, chloroquine, indocin, lisinopril, prednisone, and also solumedrol. Individuals taking these medications who notice any signs of psoriasis should seek medical advice because with corticosteroids, such as prednisone or solumedrol stopping them suddenly or even tapering off can cause a flare-up. So a doctor’s advice must be followed when attempting to discontinue use of corticosteroids.