Psoriasis

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    Last Updated: October 13, 2024

    Psoriasis is a chronic skin disease that causes patches of thick, red, scaly skin on various parts of the body. Its cause is unknown and symptoms tend to wax and wane over time.

    Psoriasis falls under the Skin, Hair, & Nails category.

    12 references on this page
    1,037 participants in 4 trials and 2 meta-analyses

    What is psoriasis?

    Psoriasis is a chronic inflammatory skin disease where skin cells regenerate too quickly and form thick, red patches of skin with white or silver scales.[1] A 2017 study found that up to 11% of adults and 1.4% of children worldwide have psoriasis.[2]

    What are the main signs and symptoms of psoriasis?

    Psoriasis typically looks like elevated lesions that are red, dry, and have silvery scales. They can appear anywhere on the body, such as:[1]

    • Elbows
    • Knees
    • Scalp
    • Face
    • Palms
    • Feet

    How is psoriasis diagnosed?

    The diagnosis is largely clinical, based on the appearance of the rash and associated symptoms. A healthcare professional must first rule out other diseases that may cause similar symptoms. During a visit with a healthcare professional, a clinical history is acquired and a comprehensive skin evaluation is done.[3]

    What are some of the main medical treatments for psoriasis?

    Treatment is determined by the extent and severity of symptoms. Medical treatments include:

    • Topical creams (e.g. steroids and moisturizers)
    • Oral or injected medications (e.g. immunosuppressants)
    • Phototherapy (exposing skin to different wavelengths of light)

    Topical treatments are used for milder cases. If there is no response to topical treatments or for more severe cases, immunosuppressants and/or phototherapy (a treatment that uses ultraviolet light) may be used.[3]

    Have any supplements been studied for psoriasis?

    Dietary supplements are often sought out to relieve symptoms of psoriasis. Supplements with the most evidence include:

    Some studies show that the above supplements are either beneficial or ineffective. More rigorous research is needed before recommendations can be made.[4]

    How could diet affect prostate psoriasis?

    Observational studies have demonstrated that people with psoriasis consume a lower amount of foods typically found in a Mediterranean diet (e.g., olive oil, fruits, fish, nuts, and whole grains).[5][6] Research using dietary interventions found that a hypocaloric diet in overweight or obese people with psoriasis or a gluten-free diet in people with a gluten sensitivity shows the most promise for helping reduce symptoms of psoriasis.[7] It is recommended that changes in diet should be used alongside standard medical treatments.[7]

    Are there any other treatments for psoriasis?

    There is some weak evidence that saltwater baths combined with phototherapy is effective. However, these findings are inconclusive and further research is required.[8] There are also some small studies suggesting that meditation can help alleviate some symptoms.[9]

    What causes psoriasis?

    Psoriasis is thought to be caused by an excessive immune response, which results in an overabundance of skin cells regenerating. The development of psoriasis includes a combination of genetic, environmental, and psychological components.[3]

    Examine Database: Psoriasis

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    Frequently asked questions

    What is psoriasis?

    Psoriasis is a chronic inflammatory skin disease where skin cells regenerate too quickly and form thick, red patches of skin with white or silver scales.[1] A 2017 study found that up to 11% of adults and 1.4% of children worldwide have psoriasis.[2]

    Are there other types of psoriasis?

    The most common type of psoriasis is called plaque psoriasis. However, there are other types of psoriasis that others may experience.

    Guttate psoriasis, which affects approximately 2% of people with psoriasis, is characterized by small (3–5 mm) confetti-like red, scaly patches. A common cause is an acute infection such as strep throat.[3]

    Erythrodermic psoriasis is a life-threatening form of psoriasis which presents as red, peeling skin that covers nearly the entire body. As a result, people will experience severe electrolyte imbalances, fluid loss, low body temperature, and severe skin shedding. If untreated, this can lead to shock (decreased blood flow which can result in organ failure) or life-threatening infection.[11]

    Pustular psoriasis causes pus filled blisters on the hands, feet, or all over the body. This form of psoriasis can be caused by a multitude of factors including genetics, stopping steroid medications too quickly, pregnancy, or infection.[3]

    What is the relationship between psoriasis and psoriatic arthritis?

    Approximately 30% of people with psoriasis are at risk of developing a disease called psoriatic arthritis. This form of arthritis results in joint stiffness, pain, and swelling. Treatments include Non-steroidal anti-inflammatory drugs (NSAIDs) and immunosuppressant medications. This disease can impair quality of life and lead to destruction of affected joints if left untreated.[12]

    For an accurate diagnosis, the Classification of Psoriatic Arthritis (CASPAR) criteria is often used. Three points from the following five criteria (bolded) must be met for a diagnosis of psoriatic arthritis:[12]

    CriteriaPoints
    Evidence of psoriasis
    Current psoriasis2
    Personal history of psoriasis1
    Family history of psoriasis1
    Nail dystrophy (splitting, pitting, or thickening of the nails)1
    Negative rheumatoid factor test (a blood marker used to diagnose rheumatoid arthritis)1
    Dactylitis (swelling of a finger)
    Current dactylitis1
    Personal history of dactylitis1
    Extra bone formation near joints of the hand or foot (confirmed by x-ray)1
    What are the main signs and symptoms of psoriasis?

    Psoriasis typically looks like elevated lesions that are red, dry, and have silvery scales. They can appear anywhere on the body, such as:[1]

    • Elbows
    • Knees
    • Scalp
    • Face
    • Palms
    • Feet
    What is the difference between psoriasis and eczema?

    Since both psoriasis and eczema can present as dry, red, and scaly rashes, they are often confused with one another. However, they differ significantly.

    Psoriasis is caused by an over-activation of the immune system, which results in excessive proliferation of keratinocytes (cells that help regenerate skin) and inflammatory molecules (cytokines). This immune cascade results in distinct areas of thick, red, and scaly patches on the skin.[3]

    On the other hand, eczema is caused by immune hypersensitivity (often triggered by allergens) and a dysfunctional skin barrier. Although eczema also presents as dry, red, and scaly skin, people often experience severe itching. This leads to scratching, which results in a vicious cycle that worsens the rash.[10]

    How is psoriasis diagnosed?

    The diagnosis is largely clinical, based on the appearance of the rash and associated symptoms. A healthcare professional must first rule out other diseases that may cause similar symptoms. During a visit with a healthcare professional, a clinical history is acquired and a comprehensive skin evaluation is done.[3]

    What are some of the main medical treatments for psoriasis?

    Treatment is determined by the extent and severity of symptoms. Medical treatments include:

    • Topical creams (e.g. steroids and moisturizers)
    • Oral or injected medications (e.g. immunosuppressants)
    • Phototherapy (exposing skin to different wavelengths of light)

    Topical treatments are used for milder cases. If there is no response to topical treatments or for more severe cases, immunosuppressants and/or phototherapy (a treatment that uses ultraviolet light) may be used.[3]

    Have any supplements been studied for psoriasis?

    Dietary supplements are often sought out to relieve symptoms of psoriasis. Supplements with the most evidence include:

    Some studies show that the above supplements are either beneficial or ineffective. More rigorous research is needed before recommendations can be made.[4]

    How could diet affect prostate psoriasis?

    Observational studies have demonstrated that people with psoriasis consume a lower amount of foods typically found in a Mediterranean diet (e.g., olive oil, fruits, fish, nuts, and whole grains).[5][6] Research using dietary interventions found that a hypocaloric diet in overweight or obese people with psoriasis or a gluten-free diet in people with a gluten sensitivity shows the most promise for helping reduce symptoms of psoriasis.[7] It is recommended that changes in diet should be used alongside standard medical treatments.[7]

    Are there any other treatments for psoriasis?

    There is some weak evidence that saltwater baths combined with phototherapy is effective. However, these findings are inconclusive and further research is required.[8] There are also some small studies suggesting that meditation can help alleviate some symptoms.[9]

    What causes psoriasis?

    Psoriasis is thought to be caused by an excessive immune response, which results in an overabundance of skin cells regenerating. The development of psoriasis includes a combination of genetic, environmental, and psychological components.[3]

    References

    1. ^The content of this page was partially adapted from MedlinePlus of the National Library of Medicine
    2. ^I M Michalek, B Loring, S M JohnA systematic review of worldwide epidemiology of psoriasisJ Eur Acad Dermatol Venereol.(2017 Feb)
    3. ^April W Armstrong, Charlotte ReadPathophysiology, Clinical Presentation, and Treatment of Psoriasis: A ReviewJAMA.(2020 May 19)
    4. ^Naoko Kanda, Toshihiko Hoashi, Hidehisa SaekiNutrition and PsoriasisInt J Mol Sci.(2020 Jul 29)
    5. ^Céline Phan, Mathilde Touvier, Emmanuelle Kesse-Guyot, Moufidath Adjibade, Serge Hercberg, Pierre Wolkenstein, Olivier Chosidow, Khaled Ezzedine, Emilie SbidianAssociation Between Mediterranean Anti-inflammatory Dietary Profile and Severity of Psoriasis: Results From the NutriNet-Santé CohortJAMA Dermatol.(2018 Sep 1)
    6. ^Luigi Barrea, Nicola Balato, Carolina Di Somma, Paolo Emidio Macchia, Maddalena Napolitano, Maria Cristina Savanelli, Katherine Esposito, Annamaria Colao, Silvia SavastanoNutrition and psoriasis: is there any association between the severity of the disease and adherence to the Mediterranean diet?J Transl Med.(2015 Jan 27)
    7. ^Adam R Ford, Michael Siegel, Jerry Bagel, Kelly M Cordoro, Amit Garg, Alice Gottlieb, Lawrence J Green, Johann E Gudjonsson, John Koo, Mark Lebwohl, Wilson Liao, Arthur M Mandelin 2nd, Joseph A Markenson, Nehal Mehta, Joseph F Merola, Ronald Prussick, Caitriona Ryan, Sergio Schwartzman, Evan L Siegel, Abby S Van Voorhees, Jashin J Wu, April W ArmstrongDietary Recommendations for Adults With Psoriasis or Psoriatic Arthritis From the Medical Board of the National Psoriasis Foundation: A Systematic ReviewJAMA Dermatol.(2018 Aug 1)
    8. ^Frank Peinemann, Marco Harari, Sandra Peternel, Thalia Chan, David Chan, Alexander M Labeit, Thilo GambichlerIndoor salt water baths followed by artificial ultraviolet B light for chronic plaque psoriasisCochrane Database Syst Rev.(2020 May 5)
    9. ^A Caresse Gamret, Alexandra Price, Raymond M Fertig, Hadar Lev-Tov, Anna J NicholsComplementary and Alternative Medicine Therapies for Psoriasis: A Systematic ReviewJAMA Dermatol.(2018 Nov 1)
    10. ^David Boothe W, Tarbox JA, Tarbox MBAtopic Dermatitis: Pathophysiology.Adv Exp Med Biol.(2017)
    11. ^Reynolds KA, Pithadia DJ, Lee EB, Liao W, Wu JJA systematic review of treatment strategies for erythrodermic psoriasis.J Dermatolog Treat.(2021-Feb)
    12. ^Ritchlin CT, Colbert RA, Gladman DDPsoriatic Arthritis.N Engl J Med.(2017-03-09)

    Examine Database References

    1. Psoriasis Symptoms - Allan SJ, Kavanagh GM, Herd RM, Savin JAThe effect of inositol supplements on the psoriasis of patients taking lithium: a randomized, placebo-controlled trialBr J Dermatol.(2004 May)
    2. Psoriasis Symptoms - Padilla HC, Laínez H, Pacheco JAA new agent (hydrophilic fraction of polypodium leucotomos) for management of psoriasisInt J Dermatol.(1974 Sep-Oct)
    3. Psoriasis Symptoms - Sadeghian G, Ziaei H, Nilforoushzadeh MATreatment of localized psoriasis with a topical formulation of zinc pyrithioneActa Dermatovenerol Alp Panonica Adriat.(2011)
    4. Psoriasis Symptoms - Gok Metin Z, Helvaci A, Gulbahar Eren MEffects of Aloe vera in adults with mucocutaneous problems: A systematic review and meta-analysis.J Adv Nurs.(2021-Mar)
    5. Psoriasis Symptoms - Zhu Y, Xu F, Chen H, Zheng QThe efficacy and safety of probiotics in the adjuvant treatment of psoriasis: a systematic review and meta-analysis of randomized controlled trials.Front Med (Lausanne).(2024)
    6. Total cholesterol - Morken T, Bohov P, Skorve J, Ulvik R, Aukrust P, Berge RK, Livden JKAnti-inflammatory and hypolipidemic effects of the modified fatty acid tetradecylthioacetic acid in psoriasis--a pilot studyScand J Clin Lab Invest.(2011 Jul)