Psoriasis and Your Skin
  Contributed by: Michelle Juenemann, Pharm.D. Candidate
                        KU School of Pharmacy

What is psoriasis?
Psoriasis is a life long, immune mediated, genetic disease that is clearly visible in the skin and/or the joints. It most frequently appears on the scalp, elbows, knees, and torso, but can occur anywhere on the body.  Lesions are usually symmetric, occurring on the same location on both the left and right sides of the body.  Psoriasis can develop at any age, but is most common in people between the ages of 15 to 35.  According to the National Institutes of Health (NIH), between 5.8 and 7.5 million Americans and 125 million people worldwide have psoriasis.

What causes psoriasis?
The exact cause of psoriasis is unknown, but most researchers agree that the immune system is accidentally triggered, speeding up the growth cycle of the skin cells.  A usual skin cell matures and sloughs off the body in about 25-30 days, where as a psoriatic skin cell will mature in approximately 3-4 days and move to the surface of the skin.  When at the surface, the cells continually pile up and form lesions instead of shedding like a normal cell would.  Psoriasis is not contagious.  Certain people are predisposed to developing psoriasis because of their genetic makeup.  A "trigger" such as emotional stress, injury to the skin, some types of infection and reaction to certain drugs is usually required to make psoriasis appear. 

Is all psoriasis alike?
No, the degree of the disease and the response to treatment varies from person to person.  There are various forms of psoriasis including plaque, guttate, pustular, inverse, and erythrodermic.  Each form has very distinct characteristics and can range from mild to moderate or even severe.

• Plaque psoriasis affects approximately 80 percent of the patients with psoriasis making it the most prevalent form.  It is characterized by inflamed, red, raised lesions that are covered by a silvery, white scale.
  
• Guttate psoriasis usually comes on quickly, starting in childhood or young adulthood.  It normally appears as small, red, individual spots on the

trunk or limbs.

• Pustular psoriasis is generally seen in adults.  It is usually recognized by white pustules surrounded by red skin.
  
• Inverse psoriasis tends to be found in the skin folds of the body.  This type of psoriasis is more common in individuals with deep skin folds and those who are overweight. 
  
• Erythrodermic psoriasis usually affects most of the patient's body surface and is considered the inflammatory form.  This form is set apart from the other types of psoriasis by the periodic widespread, fiery redness of the skin that is accompanied by severe pain and itching.
  

• Topical treatments--Topical treatments are usually considered first line treatment.  They help to reduce inflammation and slow down the excessive cell production caused by psoriasis.  Products containing coal tar and salicylic acid are commonly used.
  
• Phototherapy--Patients undergo treatments where their skin is exposed to wavelengths of ultraviolet light.  There are two types of phototherapy, UVB and PUVA.  With UVB therapy patients are exposed to an artificial UVB light source for a scheduled, specific amount of time, usually at their physician's office.  PUVA combines exposure to an ultraviolet A light source along with light-sensitizing medication.  UVA alone is generally not used to treat psoriasis, but the combination is effective.
  
• Systemic medications--These are prescription medications that affect the whole body.  Systemics are usually reserved for those who didn't respond or have success with the topical treat

ments or phototherapy.  Patients should ask their doctor which prescription medication is right for them based on the type of psoriasis they have.

• Alternative approaches--There are many unconventional treatments that are being utilized to treat psoriasis; however they haven't been studied to the same extent as the traditional medical regimens.  Patients are trying a variety of things such as acupuncture, magnets, meditation, and herbal remedies.  There are also alternative topical treatments that have helped patients in treating their psoriasis.  Aloe, tea tree oil, evening primrose oil, capsaicin, and oats are more popular among the different treatment options available that seem to help most patients who suffer from psoriasis.