There are over 6.7 million adults in the United States who have psoriasis disorders, as of 2017.1
Psoriasis is a chronic autoimmune disease that may cause various symptoms but is most often characterized by patches of abnormal skin. The most common type of psoriasis is plaque psoriasis which makes up about 90% of cases, with 20-30% suffering from moderate to severe symptoms.2 Symptoms are typically red, inflamed, itchy, and scaly skin patches or “plaques” that may appear
locally or throughout the whole body. Other symptoms of psoriasis include psoriatic arthritis(PsA) and the pitting of nails (small pin sized depressions in the toe or fingernails).
In most cases, psoriasis can be diagnosed in through medical history or a physical examination. Your physician can usually diagnose the condition by visually examining the skin, scalp, and nails. In some cases, a biopsy can be taken to eliminate other possible skin conditions.3
Although there is no cure for psoriasis, there are a number of options to treat and maintain the symptoms associated with the disease. Treatments for psoriasis aim to stop skin cells from growing too rapidly, which also reduces plaque formation and inflammation. There are three main types of treatments for psoriasis disorders: topical, phototherapy (light treatment), and systemic (medicines are taken by mouth or injection).1
TOPICAL DRUGS FOR PSORIASIS
Topical creams and ointments may be used to effectively treat mild to moderate cases of psoriasis.
Anti-inflammatory corticosteroids can be used to suppress the underlying immune system mechanism that causes excess skin growth. Effective treatment can reduce symptoms including inflammation and itching. Topical corticosteroids come in varying strengths which can be used appropriately on parts of the body with different sensitivity. Constant use of corticosteroids can lead to thinning of the skin and reduced effectiveness over time. Therefore, they are generally prescribed to treat outbreaks as opposed to a daily application.6
Vitamin D analogues or synthetic vitamin D can also be used to treat plaque psoriasis. Calcipotriene and Calcipotriene scalp solution (Dovonex)4 is a form of vitamin D3 that slows down the rate of cell growth, removes scales, and flattens lesions caused by plaque psoriasis. Calcipotriene has no serious side effects but can cause irritation on unaffected skin.5
Topical retinoids and other vitamers of vitamin A help regulate DNA activity in skin cells and decrease inflammation. Common retinoids are used to treat skin damage caused by sunburn and acne, but some are prescribed specifically to treat psoriasis. Common side effects include irritation and sensitivity to sunlight.
Salicylic acid shampoos and solutions can be used to help remove dead skin cells and reduce scaling. It can be used in conjunction with topical corticosteroids to remove plaques and prevent them from forming again.
Coal tar therapy products have a variety of benefits including anti-inflammatory, anti-scaling, and anti-itching properties. Coal tar is a byproduct of the manufacturing process of petroleum products and coal. Mild coal tar extracts are often used in shampoos and solutions used to treat severe scalp psoriasis. Coal tar products can help break down a protein called keratin in the skin which can help prevent the hardening of the skin and the formation of plaques.
Moisturizers including creams, lotions, and ointments can alleviate itching and skin dryness.
PHOTOTHERAPY (LIGHT TREATMENT) FOR PSORIASIS
Phototherapy for psoriasis involves the repeated exposure to natural or artificial ultraviolet (UV) light to treat related inflammation conditions. It is often used as a second-line treatment for psoriasis when topical treatments are not sufficient. Phototherapy usually involves a course of repeated treatment over the course of weeks or months. There are different types of UV rays that can be utilized in phototherapy.7
Ultraviolet B (UVB) consists of short wavelength UV rays. They only penetrate the first layers of the skin and are associated with sunburn.
Ultraviolet A (UVA) consists of longer wavelength UV rays. They penetrate deeper than UVB and are associated with the tanning of the skin. Unlike UVB, which can be used by itself to treat psoriasis, UVA is used in conjunction with a chemical called psoralen. Psoralen is plant-based and sensitizes the skin, allowing UVA phototherapy to be effective. The use of psoralen and UVA together is called PUVA.6
UVB phototherapy, or broadband therapy, can be used to treat localized patches of psoriasis, generalized psoriasis, and psoriasis that is resistant to topical treatments.
PUVA phototherapy is used to penetrate deeper and is a more aggressive treatment used to treat more severe cases of psoriasis.
Phototherapy should only be administered by a doctor. Improper exposure to UV light can cause sunburn, increased risk of skin cancer, and the worsening of psoriasis symptoms.1
SYSTEMIC TREATMENTS FOR PSORIASIS
Systemic treatments for psoriasis involve medications taken orally or by injection. They are often used to treat severe cases of psoriasis. Systemic treatments often have severe side-effects and are usually used for short periods of time such as treating acute outbreaks.
Systemic retinoids, not to be confused with topical retinoids, can be used to reduce the overproduction of skin cells. They are associated with severe birth defects. Women who take systemic retinoids should avoid pregnancy for several years after taking the medication.
Cyclosporine is a medicine taken orally, which suppresses the immune system to slow the rapid growth of skin cells. Cyclosporine can quickly clear psoriasis symptoms, but the improvement stops when treatment is ceased. Side effects include kidney damage and high blood pressure. treatment is ceased. Side effects include kidney damage and high blood pressure.
Methotrexate, similarly to cyclosporine, suppresses the immune system. It can be taken orally as a pill or through an injection. Methotrexate can generally be tolerated at low doses, but continued use can lead to liver damage and lower production of red blood cells, white blood cells, and clot-enhancing platelets.1
Other systemic treatments include drugs that alter the immune system or biological response. They include etanercept (Enbrel), infliximab (Remicade), adalimumab (Humira) and ustekinumab (Stelara).6 They work by blocking certain underlying immune system cells responses that cause inflammation and are linked to other symptoms of psoriasis. People taking these medications must be closely monitored because side effects include increased risk of infection and the possible contribution to other diseases including central nervous system disorders, blood diseases, cancer, and lymphoma.1
Patients with psoriasis should consult with their physician to explore treatment options based on their medical history and severity of their symptoms.
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (2017) Questions and Answers About Psoriasis. Available at: https://www.niams.nih.gov/health_info/psoriasis/ (Accessed: 15 May 2017).
- National Center for Biotechnology Information (2008) Moderate and severe plaque psoriasis: cost-of-illness study in Italy . Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2504078/ (Accessed: 15 May 2017).
- Mayo Foundation for Medical Education and Research (2015) Psoriasis: Tests and Diagnosis. Available at: http://www.mayoclinic.org/diseases-conditions/psoriasis/basics/tests-diagnosis/con-20030838a (Accessed: 15 May 2017).
- LEO Laboratories Ltd. (2007) Dovonex® (calcipotriene solution) . Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2007/020611s007,020554s007,020273s009lbl.pdf (Accessed: 15 May 2017).
- The Psoriasis and Psoriatic Arthritis Alliance (2017) Vitamin D analogues: Calcipotriol Available at: http://www.papaa.org/vitamin-d-analogues/calcipotriol (Accessed: 15 May 2017).
- Mayo Foundation for Medical Education and Research (2015) Psoriasis: Treatments and Drugs. Available at: http://www.mayoclinic.org/diseases-conditions/psoriasis/basics/treatment/con-20030838 (Accessed: 15 May 2017).
- The Psoriasis and Psoriatic Arthritis Alliance (2017) Psoriasis and Phototherapy Available at: http://www.papaa.org/further-information/psoriasis-and-phototherapy (Accessed: 15 May 2017).