Psoriasis Causes and Triggers
The exact cause of psoriasis is unknown, although scientists believe that the immune system and genetic factors
are involved. It's thought that at lease 10% of the general population inherits one or more genetic mutations
which create a predisposition to psoriasis. In order for a person to develop psoriasis, there must be a combination
of genes that predispose to psoriasis along with exposure to specific external trigger
Your immune system protects your body against disease and produces antibodies that attack germs and viruses.
However, with psoriasis, antibodies called T cells, start to attack healthy skin cells by mistake. The immune
system responds by increasing the production of new skin cells. Normally skin cells are created and die in 28 to 30
days, but with psoriasis, the cycle of skin production becomes faster and faster and skin cells are created and die
in five to six days. This causes the dead skin cells to build up on the surface of the skin creating
thick scaly patches.
Not everyone who has the specific genes goes on to develop psoriasis. Many people find that
the symptoms start or become worse because of certain triggers. The main triggers for psoriasis are:
- Alcohol. Even though psoriasis may be aggravated by excessive alcohol, the role it plays
is uncertain. It could be that the toxic effect of alcohol compromises the liver's ability to remove
poisons and toxins from the body effectively. Another possibility is that alcohol can cause the body to become
dehydrated, thereby making the skin worse. Alcohol can also cause a deficiency in the antioxidant vitamins A
and E which may lead to oxidation damage to skin cells.
- Smoking. Research has found that heavy smokers have greater risk of triggering psoriasis.
It is thought that toxins in cigarette smoke may affect the part of the immune system associated with
- Streptococcal bacteria. It is thought that a streptococcal bacterium which causes
tonsillitis or ‘strep’ throat is involved in guttate psoriasis which develops commonly in children and young
adults. However, most people with who have streptococcal throat infections do not develop psoriasis.
- HIV infection. HIV infection and other diseases of the immune system can cause psoriasis
to flare up or to appear for the first time.
- Injury to the skin. Often lesions can appear in the area of an skin injury such as
scars, scratches, insect bites or sunburn. This phenomenon is called the Koebner response and the symptoms can
appear between 10 to 14 days after a trauma to the skin, and even up to several years later.
- Medication. Certain medications such as beta blockers, non-steroid anti-inflammatory drugs
and anti-malarial drugs can trigger psoriasis.
- Stress. As with other skin problems, stress can worsen psoriasis and increase itching.
Many people can trace their first outbreak to a time of worry and stress. Excessive and long-term stress can
cause havoc on the skin as it effects all the systems of the body, especially the immune system and
its important functions in protecting the body against disease.
- Weather. Weather is a strong factor in triggering psoriasis. Cold, dry weather commonly
starts a psoriasis flare-up, and hot, damp, sunny weather improves psoriasis symptoms. However, in some
cases, sunshine can make the symptoms worse.
These are the main psoriasis causes and triggers. You should avoid them where possible.