Psoriasis - Western SummaryWestern Medicine Summary

Western Medicine

Western Summary

Psoriasis is a chronic, inflammatory skin disease characterized by red and scaly skin lesions that can affect the skin, hair, and nails. It can either be localized to small, concentrated areas or spread out over the entire body. Studies in Australia, Europe, and the United States have estimated that psoriasis is found in one to five percent of the general population.[1] Psoriasis is thought to be due to an imbalance in the immune system that leads to areas of increased inflammation, manifesting predominately on the skin. Due to the systemic immune effects, psoriasis may also affect a person’s joints,[2] cardiovascular system,[3] and psychological state.[2,4,5]

Treatment Philosophy

Treatment for psoriasis focuses on decreasing the underlying inflammation causing the lesions. Treatment options include phototherapy, and topical, oral, and injectable medications. Fewer and/or more mild lesions are treated with topical anti-inflammatories, most commonly topical steroids. If psoriasis affects the nails or joints topical medications will not be sufficient and oral or injection medications are necessary. If psoriasis lesions are more diffuse, covering large areas of the body, oral or injection medication or light-based therapies may be used. Oral and injection medications target various parts of the pathway to inflammation in psoriasis. Additionally, it is important to try to prevent flares by avoiding known triggers (smoking, alcohol, poor diet).


Psoriasis often appears as red skin plaques with silvery-white scales found on the body or scalp. The affected skin can itch, burn, become scaly, or have no associated symptoms at all. There are several forms of psoriasis:

  •  Guttate psoriasis: small scaly rain drops on the skin
  •  Pustular psoriasis: pus-filled bumps known as pustules
  •  Hand and foot psoriasis: scaling of only hands and feet
  •  Nail psoriasis: pitting or yellowing of the nails.
  •  Inverse psoriasis: red patches or plaques in the armpits, groin, and under the breasts.
  •  Psoriatic arthritis: beyond affecting skin, inflammation of the joints is a condition known as psoriatic arthritis causing joint pain and/or deformities if untreated


The exact cause of psoriasis is still under investigation, but the disease likely results from a combination of both genetic and environmental factors. The perpetuating factor in psoriasis is underlying inflammation. This inflammation causes numerous inflammatory cells to infiltrate the skin and skin cells to rapidly proliferate leading to a defective skin barrier and the visible skin lesions. The immune system is effectively on overdrive in psoriasis and may affect other parts of the body including the joints and the cardiovascular system.

Risk Factors

Your body 

  • Age: Psoriasis most commonly begins in adolescence and young adulthood but can occur at any age.
  • Genetics: There are several abnormal genes associated with the development of psoriasis,[6] which can partially explain why identical twins are more likely to have psoriasis than fraternal twins.[7]
  • Autoimmunity: Psoriasis is considered an autoimmune disease; therefore people with a personal or family history of autoimmune diseases are at greater risk of developing psoriasis.
  • Infection: Certain infections, such as strep throat, can trigger a psoriasis flare, especially guttate psoriasis.[8]
  • Injuries: A process known as koebnerization can cause psoriasis to develop over injured skin, such as from scratching or surgery sites.



  • Alcohol: Researchers have found a link between alcohol consumption and psoriasis. People with psoriasis tend to drink more alcohol, and alcohol can in turn worsen psoriasis,[9] leading to a vicious cycle.
  • Smoking: Smoking has been found to be an independent risk factor for the development of psoriasis.[10]
  • Weight gain: Increased weight and obesity are linked to worsened psoriasis.[11]



  • Medications: Several medications have been known to cause psoriasis to flare, including the use of beta-blocker (a family of blood pressure medication) and lithium (a medication to help stabilize the mood).[12]
  • Systemic steroids: Although topical steroids are effective for treating psoriasis, systemic (oral and IV forms) steroids may cause a severe psoriasis flare after the treatments are stopped.[13]


  • Climate: Studies have shown that psoriasis worsens during the wintertime (in the Northern Hemisphere).[14]


Topical medications

Topical treatments are very effective for visible lesions and can treat psoriasis affecting a smaller overall area of the body. However, topical therapies are not helpful in improving joint inflammation and are minimally helpful in treating nail changes.

  • Topical steroids: main treatment for psoriasis of the skin (but not joints or nails).
  • Topical vitamin D: can also be used either alone or in combination with topical steroids.
  • Topical retinoids: (a medication in the vitamin A family) these are only occasionally used as they may cause more redness and dryness.
  • Tar-based creams and shampoos: can be very effective but have an odor that some may be averse to.

Oral and injected systemic medications

Oral or injectable medications may be used for more severe and widespread forms of psoriasis. Some of these medications suppress the characteristic over-activation of the immune system in psoriasis, and may help with treating psoriatic arthritis and nail changes.

  • Oral retinoids: acitretin is the only medication in this class.
  • Oral medications for suppressing the immune system: Methotrexate, azathioprine, and cyclosporine can all decrease overall inflammation leading to improvement in psoriasis symptoms.
  • Oral apremilast: inhibits a psoriasis-causing molecule in the inflammatory pathway (phosphodiesterase- 4).
  • Biologics: newer class of medications that are typically administered by injection or IV. They directly block more specific inflammatory signals. These signals, such as the tumor necrosis factor (TNF) and interleukins, are molecules that are released by the immune system leading to increased inflammation and in turn, worsening of psoriasis. Some of these medications include etanercept, adalimumab, infliximab, ustekinumab, secukinumab, ixekizumab,


  • Ultraviolet light therapy: Several ultraviolet light-based therapies are used in the treatment of psoriasis. Just like topical medications light therapies are not effective in treating psoriatic arthritis and are minimally helpful in treating nail changes.
  • Narrowband ultraviolet type B therapy: Studies have shown that a specific wavelength of ultraviolet light (311-313 nanometers) is effective for improving psoriasis.[15,16]
  • Psolaren-based ultraviolet type A therapy: Another form of ultraviolet therapy called as psoralens.

Nutrition and diet

  • Antioxidants: The use of antioxidant supplementation has not produced consistent results in studies.[9] So the jury is still out on the benefit of antioxidants in psoriasis. However, one study have shown that in people who are hospitalized for severe psoriasis, adding selenium, vitamin E, and coenzyme Q to conventional treatment showed improvement in psoriasis compared to placebo (no antioxidant supplement).[17]
  • Beta-carotene: Although further research is needed to verify any benefit of beta-carotene for psoriasis, one study found psoriasis can improve by using a beta-carotene-based supplement.[18]
  • Vitamin D: Although more research is indicated, studies have shown that patients with psoriasis and psoriatic arthritis have lower levels of vitamin D and may benefit from vitamin D supplementation.


  • Weight loss: Weight loss has been shown to improve psoriasis in people who are overweight.[19]
  • Smoking: People with psoriasis tend to smoke more often[10], and smoking can worsen psoriasis, therefore smoking cessation is encouraged.
  1. Parisi R, Symmons DP, Griffiths CE, et al. Global epidemiology of psoriasis: a systematic review of incidence and prevalence. J Invest Dermatol. 2013; 133(2):377-385; PMID: 23014338 Link to research.
  2. Truong B, Rich-Garg N, Ehst BD, et al. Demographics, clinical disease characteristics, and quality of life in a large cohort of psoriasis patients with and without psoriatic arthritis. Clin Cosmet Investig Dermatol. 2015; 8:563-569; PMID: 26622188 Link to research.
  3. Ogdie A, Yu Y, Haynes K, et al. Risk of major cardiovascular events in patients with psoriatic arthritis, psoriasis and rheumatoid arthritis: a population-based cohort study. Ann Rheum Dis. 2015; 74(2):326-332; PMID: 25351522 Link to research.
  4. Connor CJ, Liu V, Fiedorowicz JG. Exploring the Physiological Link between Psoriasis and Mood Disorders. Dermatol Res Pract. 2015; 2015:409637; PMID: 26550011 Link to research.
  5. Cohen BE, Martires KJ, Ho RS. Psoriasis and the Risk of Depression in the US Population: National Health and Nutrition Examination Survey 2009-2012. JAMA Dermatol. 2015;10.1001/jamadermatol.2015.3605PMID: 26421371 Link to research.
  6. Tsoi LC, Spain SL, Knight J, et al. Identification of 15 new psoriasis susceptibility loci highlights the role of innate immunity. Nat Genet. 2012; 44(12):1341-1348; PMID: 23143594 Link to research.
  7. Farber EM, Nall ML, Watson W. Natural history of psoriasis in 61 twin pairs. Arch Dermatol. 1974; 109(2):207-211; PMID: 4814926 Link to research.
  8. Gudjonsson JE, Thorarinsson AM, Sigurgeirsson B, et al. Streptococcal throat infections and exacerbation of chronic plaque psoriasis: a prospective study. Br J Dermatol. 2003; 149(3):530-534; PMID: 14510985 Link to research.
  9. Murzaku EC, Bronsnick T, Rao BK. Diet in dermatology: Part II. Melanoma, chronic urticaria, and psoriasis. J Am Acad Dermatol. 2014; 71(6):1053 e1051-1053 e1016; PMID: 25454037 Link to research.
  10. Armstrong AW, Harskamp CT, Dhillon JS, et al. Psoriasis and smoking: a systematic review and meta-analysis. Br J Dermatol. 2014; 170(2):304-314; PMID: 24117435 Link to research.
  11. Fleming P, Kraft J, Gulliver WP, et al. The Relationship of Obesity With the Severity of Psoriasis: A Systematic Review. J Cutan Med Surg. 2015; 19(5):450-456; PMID: 26271963 Link to research.
  12. Dika E, Varotti C, Bardazzi F, et al. Drug-induced psoriasis: an evidence-based overview and the introduction of psoriatic drug eruption probability score. Cutan Ocul Toxicol. 2006; 25(1):1-11; PMID: 16702050 Link to research.
  13. Baker H. Corticosteroids and pustular psoriasis. Br J Dermatol. 1976; 94 suppl 12:83-88; PMID: 1268081 Link to research.
  14. Pascoe VL, Kimball AB. Seasonal variation of acne and psoriasis: A 3-year study using the Physician Global Assessment severity scale. J Am Acad Dermatol. 2015; 73(3):523-525; PMID: 26282801 Link to research.
  15. Barbagallo J, Spann CT, Tutrone WD, et al. Narrowband UVB phototherapy for the treatment of psoriasis: a review and update. Cutis. 2001; 68(5):345-347; PMID: 11766120 Link to research.
  16. Walters IB, Burack LH, Coven TR, et al. Suberythemogenic narrow-band UVB is markedly more effective than conventional UVB in treatment of psoriasis vulgaris. J Am Acad Dermatol. 1999; 40(6 Pt 1):893-900; PMID: 10365919 Link to research.
  17. Kharaeva Z, Gostova E, De Luca C, et al. Clinical and biochemical effects of coenzyme Q(10), vitamin E, and selenium supplementation to psoriasis patients. Nutrition. 2009; 25(3):295-302; PMID: 19041224 Link to research.
  18. Greenberger S, Harats D, Salameh F, et al. 9-cis-rich beta-carotene powder of the alga Dunaliella reduces the severity of chronic plaque psoriasis: a randomized, double-blind, placebo-controlled clinical trial. J Am Coll Nutr. 2012; 31(5):320-326; PMID: 23529989 Link to research.
  19. Upala S, Sanguankeo A. Effect of lifestyle weight loss intervention on disease severity in patients with psoriasis: a systematic review and meta-analysis. Int J Obes (Lond). 2015; 39(8):1197-1202; PMID: 25920774 Link to research.