Psoriasis is chronic skin disease (disorder of the immune system), characterized by thick, red, silvery, scaled patches. Researcher believe abnormal immune system produces too many of the immune cells, called “T cells,” in the skin. These “T cells” trigger the inflammation and excessive skin cell reproduction seen in people with psoriasis. The disease effects both male and female equally, and common during the first fifteen to thirty years, however may appear later in life. About two to three percent of the population suffers from this skin disease, which is fifty percent genetically attributed. In the United States approximately 5.5 million people have this disease, and 150,000 to 260,000 new cases occur annually. This skin disease is less common in tropics and in dark skinned people. Between ten to thirty percent of those developing psoriasis, get related form of arthritis
called “psoriatic arthritis,” which causes inflammation of the joints. This skin disease is not contagious.
There are six types of psoriasis with unique symptoms. Plaque psoriasis is most common. Eighty percent of those people develop patches of raised reddish skin, covered by silver-white scale. Often seen on the elbows, knees, lower back, and scalp or anywhere on the body. Guttate psoriasis appears on the skin as small red spots, and tends to affect most of the body, but prevalent on the face, ears, and scalp. The rash appears quickly within a couple of days, and tends to disappear spontaneously or sometimes treated with medication. Usually those affected are children or young adults and may have a streptococcal infection of the throat. Erythrodermic psoriasis is least common form of psoriasis. The skin disease is characterized by widespread redness of the skin, exfoliation (shedding) of the skin, frequently severe itching and pain. Increased blood flow can be stressful to the heart. Medications include topical treatment. Also, antibiotics are sometimes administered to prevent or stop infection. The condition may worsen, requiring hospitalization, and treatment for dehydration. Postular psoriasis is uncommon form of skin disease, and appears as raised bumps on the skin that is filled with pus. Around the bumps, the skin appears reddish. This type of psoriasis is subcategorized into three types, depending on symptoms. Lesions may appear sudden (acute), long term (chronic) or somewhere between (subacute) both. Postular psoriasis of the palm and soles is usually chronic. Inverse psoriasis are bright red, smooth, and located or found in the folds of the skin, such as under the breasts, in the armpits, and near the genitals or in abdominal folds. In those locations, sweat and skin rubbing together, may cause irritation and inflamed areas. Medicated tropical creams and ointments will treat this type of psoriasis. Nail psoriasis can affect the fingernails and toenails. The appearance is a yellow red nail discoloring, looks like a drop of blood under the nail.
Methotrexate tablets taken once a week to treat psoriasis, and patients usually see improvement over one or two months. The medication is not suitable for those with liver problems or may cause irreversible damage to the liver, for some patients. Those taking the medication must avoid alcohol, which may increase risk of liver damage. Patients taking Methotrexate should have blood tests to monitor for any liver and kidney function problems. Kidneys maybe impaired, causing a toxic buildup of methotrexate in the blood, if the patient takes aspirin or aspirin like drugs. Furthermore, dehydration from fever, vomiting, diarrhea or decrease fluid intake can be dangerous, because this may prevent kidney function from normal excretion of methotrexate. Sometimes folic acid is prescribed to contract side effects of methotrexate. The medication is not advisable for pregnant women or women planning to get pregnant, because methotrexate known to cause birth defects, miscarriage or stillbirth, especially in the first three months of pregnancy. When the medication is taken for many years, has shown to have very low risk causing cancer.
Ciclosporin previously prescribed as strong immune suppressant drug, which prevents rejection of transplant organs. The medication has been linked to treating psoriasis in New Zealand. However, the medication may cause high blood pressure and kidney damage, which requires careful monitoring of blood tests. The medication has been linked developing skin cancer (squamous cell cancer).
Hydroxyurea (hydroxycarbamide) medication treats certain types of cancer, and known to treat plaque psoriasis. Medication is taken daily usually at a dose of 500 mg to one gram orally. The medication is less effective treating postular and guttate psoriasis. The medication has a low risk of liver toxicity, and no kidney toxicity, except for leukemia patients.
Corticosteroid creams (steroids), ointments, lotions or solutions are prescribed, for treating mild psoriasis. Any one of these topical agents, is graded by potency from class I (the most potent) to class VIII (the least potent). The medication is applied once or twice a day. When symptoms start to subside, the potency of the medication maybe reduced or prevents drug tolerance. Corticosteroid pills and injections are available, but are rarely applicable. Pills have the potential serious side effects, and injections often not practical, when large area of the skin is affected. Long term use of corticosteriods, can lead to irreversible thinning of the skin and decrease effectiveness. Also, corticosteriods cannot be applied around the eyes, due to the risk of developing glaucoma.
Medications available for treating psoriasis, which do not contain steroids includes Calcitriol, Tacrolimus, Systemic, Fumaric acid esters, Systemic Plus Topical and Alefacept plus topical calcipotriol. Calcitriol applied as topical form containing vitamin ‘D.’ Studies have shown most effective treating mild to moderate plaque psoriasis, on sensitive areas, including face, hairline, and body folds. Tacrolimus previously taken as pill prevents organ transplant rejection. Oral tacrolimus is available for treating severe plaque psoriasis, which does not respond to other treatment. However, limited to use in patients for severe psoriasis, because of the potency suppress the immune system. Systemic topical medication is swallowed or injected and treats psoriasis lesions. Side effects of the medication limit the use. Fumaric acid esters medication has been treating psoriasis in Germany, since 1959. Some patients may have to discontinue the medication, because of severe side effects including diarrhea, nausea, stomach pain, flushing and in some cases kidney damage. A new formulation of this medication called ‘BGOOO12,’ clinical studies in Europe revealed less likely cause diarrhea, nausea, and stomach pain. Systemic Plus Topical is a synthetic form of vitamin ‘D’ to treat psoriasis. Alefacept plus topical calcipotriol is a combination of topical medication calcitriol and Alefacept (mentioned next paragraph).
In January 2003, the Food and Drug Administration approved Amevive (Alefacept) (produced by Biogen incorporated) for the treatment of psoriasis. Astellas Pharma US (Subsidiary of Astellas Pharma Incorporated, located in Tokyo Japan) purchased the worldwide rights of Amervive from Biogen, effective March 31, 2006. The agreement continues the manufacturing by Biogen and supplying product to Astellas. The medication is administered under the supervision of a physician or dermatologist by intravenous or intramuscular injection, once per week for twelve weeks. Some patients may require additional twelve weeks, but they must wait at least twelve weeks between cycles. Studies have shown, seventy-five to fifty percent increase improvement after two cycles of treatments, than after one. Amevive is prescribed for adults with moderate to severe plaque psoriasis. The medication has not been approved for children. Amevive targets the ‘T’ cells that trigger psoriasis. During clinical trials, most common side effect was transient chills, which patients experienced after the first or second dose, but did not cause a discontinuation of the medication. Also, other common side effects include: Sore throat, dizziness, increased cough, itching, nausea, muscle aches, and injection site reaction is pain / inflammation. Patients need to have their blood tested weekly during treatment, monitoring to ensure the level of infection fighting immune cells are not reduced significantly, would postpone further treatment. Also, a suppressed immune system, increase the risk of developing cancer. Amevive should not be administered to patients having HIV, because it may increase progression of the virus (Reduces CD4+ T lymphocyte counts). Uncertainty, how the medication will effect a developing fetus or women under going treatment then get pregnant. Also, unknown if there is any side effect, when the medication passes into the breast milk in nursing women. The original cost $7,000 to $10,000: during a twelve – week course of treatments. The cost of treatment maybe reimbursed, by a patient’s insurer. Questions regarding Biogen Amevive medication by calling: 866 – AMEVIVE (866 – 263 – 8483).