Font Size
A
A
A
2
...

Psoriasis (cont.)

Psoriasis Causes

Research indicates that the disease results from a disorder in the immune system. The immune system programs the white blood cells that protect the body from infection. In psoriasis, T lymphocytes (a type of white blood cell) abnormally trigger inflammation in the skin. These T cells also cause skin cells to grow faster than normal and to pile up in raised plaques on the outer surface of the skin.

Those with a family history of psoriasis have an increased chance of having the disease. Some people carry genes that make them more likely to develop psoriasis. When both parents have psoriasis, the child has a 50% chance of developing psoriasis. About one-third of those with psoriasis can recall at least one family member with the disease.

Certain factors may trigger psoriasis.

  • Injury to the skin: Injury to the skin has been associated with plaque psoriasis. For example, a skin infection, skin inflammation, or even excessive scratching can trigger psoriasis.
  • Sunlight: Most people generally consider sunlight to be beneficial for their psoriasis. However, a small minority find that strong sunlight aggravates their condition. A bad sunburn may worsen psoriasis.
  • Streptococcal infections: Streptococcal sore throats may trigger a guttate psoriasis, a type of psoriasis that looks like small red drops on the skin.


Guttate psoriasis. Red drop-like lesions are found on the skin. This type of psoriasis usually occurs after a streptococcal (bacterial) infection. Image courtesy of Hon Pak, MD.

  • HIV: Psoriasis may worsen after an individual has been infected with HIV. However, psoriasis often becomes less active in advanced HIV infection.
  • Drugs: A number of medications have been shown to aggravate psoriasis. Some examples are as follows:
    • Lithium: Drug that may be used to treat bipolar disorder
    • Beta-blockers: Drugs that may be used to treat high blood pressure
    • Antimalarials: Drugs used to treat malaria, arthritis, and lupus.
    • NSAIDs: Drugs, such as ibuprofen (Motrin and Advil) or naproxen (Aleve), used to reduce inflammation
  • Emotional stress: Many people note an increase in their psoriasis when emotionally stressed.
  • Smoking: Cigarette smokers have an increased risk of chronic plaque psoriasis.
  • Alcohol: Alcohol is considered a risk factor for psoriasis. Even moderate intake of beer may trigger or worsen psoriasis.
  • Hormone changes: The severity of psoriasis may fluctuate with hormonal changes. Disease frequency peaks during puberty and menopause. During pregnancy, psoriatic symptoms are more likely to improve. In contrast, flares occur in the postpartum period.
Medically Reviewed by a Doctor on 10/23/2014
Medical Author:

Must Read Articles Related to Psoriasis

Guttate Psoriasis
Guttate Psoriasis Guttate psoriasis is a type of psoriasis that looks like small, salmon-pink drops on the skin. The word guttate is derived from the Latin word gutta, meaning dr...learn more >>
Iritis
Iritis The iris is a circular, pigmented membrane that provides the eye its color and forms the pupil of the eye. The iris is made up of muscular fibers that control ...learn more >>
Nail Psoriasis
Nail Psoriasis Psoriasis is a common condition. A person with psoriasis generally has patches of raised red skin with silvery scales. The affected skin may look shiny and red ...learn more >>

Patient Comments & Reviews

The eMedicineHealth doctors ask about Psoriasis:

Psoriasis - Causes

What caused your psoriasis?

Psoriasis - Effective Treatments

What kinds of treatments have been effective for your psoriasis?

Psoriasis - Symptoms

What were the symptoms of your psoriasis?

Psoriasis - Home Remedies

What home remedies have been effective for your psoriasis?




Read What Your Physician is Reading on Medscape

Psoriasis »

Psoriasis is a chronic, noncontagious, multisystem, inflammatory disorder.

Read More on Medscape Reference »


Medical Dictionary