Up to 2% of Americans suffer from psoriasis, a skin condition that leads to an intensely itchy rash with clearly defined borders and scales that resemble silvery mica. The fingernails are also frequently involved, showing pitting or thickening.
Medical treatment for psoriasis includes applications of topical steroids and peeling agents that expose the underlying skin for the steroid to contact. Ultraviolet light can also be used, sometimes combined with coal tar applications or medications called psoralens. Synthetic relatives of vitamin A and vitamin D are also used.
Evidence from two double-blind, placebo-controlled trials and one comparative trial suggest that cream made from the herb Oregon grape ( Mahonia ) may help reduce symptoms of psoriasis, although it does not seem to be as effective as standard medications.
In a double-blind study published in 2006, 200 people were given either a cream containing 10% Oregon grape extract or placebo twice a day for 3 months. 27 The results indicate that the people using Oregon grape experienced greater benefits than those in the placebo group, and the difference was statistically significant. The treatment was well tolerated; although, it caused rash or burning sensation in a few people.
Benefits were also seen in a double-blind, placebo-controlled study of 82 people with psoriasis. 11 However, the study design had a significant flaw: the treatment salve was darker in color than the placebo, possibly allowing participants to guess which was which.
Another study found that dithranol, a conventional drug used to treat psoriasis symptoms, was more effective than Oregon grape. 12 Regrettably, the authors fail to state whether this study was double-blind. Forty-nine participants applied one treatment to their left side and the other to their right for 4 weeks. Skin biopsies were then analyzed and compared with samples taken at the beginning of the study. The physicians evaluating changes in skin tissue were unaware which treatments had been used on the samples. Greater improvements were seen in the dithranol group.
A large open study in which 443 participants with psoriasis used Oregon grape topically for 12 weeks found the herb to be helpful for 73.7% of the group. 13 Without a placebo group, it's not possible to know whether Oregon grape was truly responsible for the improvement seen, but the trial does help to establish the herb's safety and tolerability.
Laboratory research suggests Oregon grape has some effects at the cellular level that might be helpful in psoriasis, such as slowing the rate of abnormal cell growth and reducing inflammation. 14,15
For more information, including dosage and safety issues, see the full Oregon grape article.
Aloe vera cream may be helpful for psoriasis, according to a double-blind study performed in Pakistan that enrolled 60 men and women with mild to moderate symptoms of psoriasis. 19 Participants were treated with either topical Aloe vera extract (0.5%) or a placebo cream, applied 3 times daily for 4 weeks. Aloe treatment produced significantly better results than placebo, and these results were said to endure for almost a year after treatment was stopped. The study authors also reported a high level of complete "cure," but what exactly they meant by this was not reported clearly.
However, a follow-up study of 40 people that attempted to replicate these results failed to find aloe more effective than placebo. 29 For more information, including dosage and safety issues, see the full Aloe article.
Capsaicin is the “hot” in cayenne pepper. Creams made from capsaicin are used to treat a number of pain-related conditions. Some evidence indicates that capsaicin cream may be helpful for psoriasis as well. A double-blind, placebo-controlled trial of almost 200 people found that use of topical capsaicin can improve itching as well as overall severity of psoriasis. 21 Benefits were also seen in a smaller double-blind trial. 22
For more information on capsaicin cream, see the Cayenne article
The evidence regarding fish oil's effectiveness for psoriasis remains incomplete and contradictory.
An 8-week, double-blind study followed 28 people with chronic psoriasis. 1 Half received 10 capsules of fish oil daily, and the other half received a placebo . By the end of the study, researchers saw significant improvement in itching, redness, and scaling, but not in the size of the psoriasis patches. However, another double-blind study followed 145 people with moderate to severe psoriasis for 4 months and found no benefit as compared to placebo. 2
For more information, including dosage and safety issues, see the full Fish Oil article.
Based on very preliminary evidence, shark cartilage20 and cetylated fatty acids have also been proposed for treatment of psoriasis. 30
Beta-carotene , barberry , burdock , chromium , cleavers , Coleus forskohlii ,goldenseal , topical licorice cream, milk thistle , red clover , selenium , taurine , vitamin E , yellow dock , and zinc are also sometimes mentioned as possible treatments for psoriasis. However, as yet, there is no meaningful evidence that they work.
A somewhat toxic natural substance called fumaric acid is sometimes recommended for psoriasis as well. Vitamin A or special forms of vitamin D taken at high levels may improve symptoms, but these are dangerous treatments that should be used only under the supervision of a physician.
People using the drug methotrexate for psoriasis frequently develop nausea, mouth sores, and other side effects. Evidence indicates that taking folate supplements may help. 23
Seal oil has shown a hint of promise for treatment of psoriatic arthritis (a type of joint pain and inflammation that can occur in association with psoriasis). 28 .
One study found that hypnosis may improve psoriasis symptoms. 26Balneotherapy (spa therapy) might also have value. 31-32
Although case reports suggest that acupuncture might be useful for psoriasis, 24 a controlled trial failed to find acupuncture more effective than fake acupuncture. 25 Another small study suggested that the Chinese herbal decoction Qinzhu Liangxue may be helpful in selected patients with psoriasis, though this finding is highly preliminary. 33
Various herbs and supplements may interact adversely with drugs used to treat psoriasis. For more information on this potential risk, see the individual drug article in the Drug Interactions section of this database.
References
1. Bittiner SB, Tucker WF, Cartwright I, et al. A double-blind, randomised, placebo-controlled trial of fish oil in psoriasis. Lancet. 1988;1:378-380.
2. Soyland E, Funk J, Rajka G, et al. Effect of dietary supplementation with very-long-chain n-3 fatty acids in patients with psoriasis. N Engl J Med . 1993;328:1812-1816.
8. Wiesenauer M, Ldtke R. Mahonia aquifolium in patients with Psoriasis vulgaris—an intraindividual study. Phytomedicine. 1996;3:231-235.
9. Gieler U, von der Weth A, Heger M. Mahonia aquifolium—a new type of topical treatment for psoriasis. J Dermatol Treat. 1995;6:31-34.
10. Augustin M, Andrees U, Grimme H, et al. Effects of Mahonia aquifolium ointment on the expression of adhesion, proliferation, and activation markers in the skin of patients with psoriasis. Forsch Komplementrmed. 1999;6(suppl 2):19-21.
11. Wiesenauer M, Ldtke R. Mahonia aquifolium in patients with Psoriasis vulgaris - an intraindividual study. Phytomedicine. 1996;3:231-235.
12. Augustin M, Andrees U, Grimme H, et al. Effects of Mahonia aquifolium ointment on the expression of adhesion, proliferation, and activation markers in the skin of patients with psoriasis. Forsch Komplementrmed. 1999;6(suppl 2):19-21.
13. Gieler U, von der Weth A, Heger M. Mahonia aquifolium - a new type of topical treatment for psoriasis. J Dermatol Treat. 1995;6:31-34.
14. Galle K, Mller-Jakic B, Proebstle A, et al. Analytical and pharmacological studies on Mahonia aquifolium. Phytomedicine. 1994;1:59-62.
15. Muller K, Ziereis K. The antipsoriatic Mahonia aquifolium and its active constituents; I. Pro- and antioxidant properties and inhibition of 5-lipoxygenase. Planta Med . 1994;60:421-424.
19. Syed TA, Ahmad SA, Holt AH, et al. Management of psoriasis with Aloe vera extract in a hydrophilic cream: a placebo-controlled, double-blind study. Trop Med Int Health . 1996;1:505-509.
20. Dupont E, Savard PE, Jourdain C, et al. Antiangiogenic properties of a novel shark cartilage extract: potential role in the treatment of psoriasis. J Cutan Med Surg. 1998;2:146-152.
21. Ellis CN, Berberian B, Sulica VI, et al. A double-blind evaluation of topical capsaicin in pruritic psoriasis. J Am Acad Dermatol. 1993;29:438-442.
22. Bernstein JE, Parish LC, Rapaport M, et al. Effects of topically applied capsaicin on moderate and severe psoriasis vulgaris. J Am Acad Dermatol. 1986;15:504-507.
23. Duhra P. Treatment of gastrointestinal symptoms associated with methotrexate therapy for psoriasis. J Am Acad Dermatol. 1993;28:466-469.
24. Liao, SJ. Acupuncture treatment for psoriasis: a retrospective case report. Acupunct Electrother Res. 1992;17:195-208.
25. Jerner B, Skogh M, Vahlquist A. A controlled trial of acupuncture in psoriasis: no convincing effect. Acta Derm Venereol (Stockh) . 1997;77:154-156.
26. Zachariae R, Oster H, Bjerring P, et al. Effects of psychologic intervention on psoriasis: a preliminary report. J Am Acad Dermatol . 1996;34:1008-1015.
27. Bernstein S, Donsky H, Gulliver W, et al. Treatment of Mild to Moderate Psoriasis with Relieva, a Mahonia aquifolium Extract-A Double-Blind, Placebo-Controlled Study. Am J Ther. 2006;13:121-126.
28. Madland TM, Bjorkkjaer T, Brunborg LA, et al. Subjective Improvement in Patients with Psoriatic Arthritis After Short-Term Oral Treatment with Seal Oil. A Pilot Study with Double Blind Comparison to Soy Oil. J Rheumatol . 2006;33:307-310
29. Paulsen E, Korsholm L, Brandrup F, et al. A double-blind, placebo-controlled study of a commercial Aloe vera gel in the treatment of slight to moderate psoriasis vulgaris. J Eur Acad Dermatol Venereol. 2005;19:326-331.
30. A Preliminary Study for the use of Celadrin™ for the Treatment of Psoriasis (September 18, 2002). Available at: http://www.celadrin.com/studies/SafetyHumans.pd . Accessed June 3, 2005.
31. Gambichler T, Tomi NS, Kreuter A. Controlled clinical trials on balneophototherapy in psoriasis. Br J Dermatol . 2006;154:802-803.
32. Dawe RS, Yule S, Cameron H, et al. A randomized controlled comparison of the efficacy of Dead Sea salt balneophototherapy vs. narrowband ultraviolet B monotherapy for chronic plaque psoriasis. Br J Dermatol . 2005;153:613-619.
33. Li FL, Li B, Xu R, et al. Qinzhu Liangxue decoction in treatment of blood-heat type psoriasis vulgaris: a randomized controlled trial. Zhong Xi Yi Jie He Xue Bao. 2008;6:586-590.
Last reviewed April 2009 by EBSCO CAM Review Board
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