Psoriasis

Topical Oregon grape is the best-evidenced psoriasis herb by a wide margin. Five randomised or controlled trials and a 2013 systematic review with meta-analysis converge on a modest but real benefit of topical M. aquifolium in mild-to-moderate plaque psoriasis, with a pooled relative risk of about 3.4 versus placebo ^{1,2,3,4,5Reference 1Bernstein et al. · 2006RCTTreatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract — a double-blind, placebo-controlled studyView study →Reference 2Gulliver et al. · 2005Clinical trialA report on three recent clinical trials using Mahonia aquifolium 10% topical cream and a review of the worldwide clinical experience with Mahonia aquifolium for the treatment of plaque psoriasisView study →Reference 3Wiesenauer et al. · 1996RCTMahonia aquifolium in patients with psoriasis vulgaris — a randomized, placebo-controlled intraindividual studyView study →Reference 4Augustin et al. · 1999RCTEffects of Mahonia aquifolium ointment on the expression of adhesion, proliferation and activation markers in the skin of patients with psoriasis — randomised controlled trialView study →Reference 5Deng et al. · 2013Meta-analysisPlant extracts for the topical management of psoriasis — a systematic review and meta-analysisView study →}. The largest single study — a double-blind, placebo-controlled RCT of a twice-daily 10% cream over 12 weeks (n=200) — improved both PASI and quality-of-life scores ^{1Reference 1Bernstein et al. · 2006RCTTreatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract — a double-blind, placebo-controlled studyView study →}.

The mechanism is unusually well matched to the disease: bark alkaloids inhibit 5- and 12-lipoxygenase, whose metabolites drive psoriatic inflammation ^{9,10Reference 9Müller et al. · 1994In vitroThe antipsoriatic Mahonia aquifolium and its active constituents; IView study →Reference 10Bezáková et al. · 1996In vitroLipoxygenase inhibition and antioxidant properties of bisbenzylisoquinoline alkaloids isolated from Mahonia aquifolium — in vitroView study →}, and the extract is antiproliferative to human keratinocytes ^{8Reference 8Müller et al. · 1995In vitroThe antipsoriatic Mahonia aquifolium and its active constituents; IIView study →} — the two things psoriasis actually consists of. The active constituents are the bisbenzylisoquinolines berbamine and oxyacanthine alongside berberine.

The effect is modest rather than transformative, trial quality is variable, and the studies test proprietary 10% creams rather than a home preparation. Tolerability across the controlled trials was good, with infrequent and minor local irritation ^{1,5Reference 1Bernstein et al. · 2006RCTTreatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract — a double-blind, placebo-controlled studyView study →Reference 5Deng et al. · 2013Meta-analysisPlant extracts for the topical management of psoriasis — a systematic review and meta-analysisView study →}. Oregon grape is also widely recommended as a sustainable alternative to goldenseal, which is at risk from over-harvest.

Sarsaparilla is the classic Western alterative for psoriasis, and its traditional reputation has begun to acquire an experimental basis. Quercetin isolated from Smilax china rhizome improved epidermal thickness and orthokeratosis in the mouse-tail model of psoriasis ^{11Reference 11Vijayalakshmi et al. · 2012AnimalScreening of flavonoid “quercetin” from the rhizome of Smilax china Linn. for anti-psoriatic activity — animal modelView study →}, and a 2024 study combining network pharmacology with an imiquimod-induced mouse model found S. glabra dampens psoriatic skin inflammation by regulating the T-cell immune response ^{12Reference 12Guo et al. · 2024AnimalIntegrated network pharmacological analysis revealed that Smilax glabra Roxb. alleviates IMQ-induced psoriatic skin inflammation through regulating T cell immune response — animal modelView study →} — which is the right target, given that psoriasis is a T-cell-driven disease.

Across its very wide geographic range, sarsaparilla has been used for a strikingly consistent triad: skin disease and psoriasis especially, systemic infection, and rheumatic complaints ^{13Reference 13Hua et al. · 2018ReviewEthnomedicine, phytochemistry and pharmacology of Smilax glabra — an important traditional Chinese medicine — reviewView study →}. These are animal models rather than human trials, and Smilax is a large genus whose species differ chemically, so results from S. china and S. glabra do not automatically transfer to the S. officinalis group sold as sarsaparilla.

Samambaia’s reputation and its evidence point in different directions. Samambaia has a human dataset — but it is for photoprotection, not psoriasis: oral extract measurably reduces UV-induced skin damage, and the standardised preparation has been reviewed repeatedly for dermatologic use ^{14,15Reference 14Winkelmann et al. · 2015ReviewPolypodium leucotomos extract: a status report on clinical efficacy and safety — reviewView study →Reference 15Zundell et al. · 2025Systematic reviewThe utility of oral Polypodium leucotomos extract for dermatologic diseases — a systematic reviewView study →}. Its older reputation as a leading psoriasis remedy rests on much thinner ground ^{14Reference 14Winkelmann et al. · 2015ReviewPolypodium leucotomos extract: a status report on clinical efficacy and safety — reviewView study →}.

The mechanistic work is relevant — the extract upregulates the NRF2 antioxidant pathway in keratinocytes and moderates UV-driven inflammation — and the proprietary extract Anapsos was studied in psoriasis patients historically, which is how its incidental cognitive effects were first noticed. Its best skin evidence lies elsewhere, and its psoriasis use is plausible but untested.

Burdock is the archetypal Western alterative, and the herb most consistently named for chronic scaly skin disease across Anglo-American herbal practice. The root is taken over weeks to months — not for days — for psoriasis, eczema and acne, on the traditional reasoning that persistent skin disease reflects sluggish elimination and benefits from gentle, sustained support of the liver, bowel and kidneys. It is a food as well as a medicine (gobo in Japanese cooking), which is part of why long courses are unremarkable. There is no controlled trial for this indication; the case rests on a long, coherent and well-documented tradition.

Chickweed is the traditional first reach for an itchy, irritated plaque, used as a cream, salve or poultice. Its reputation is specifically for relief of itch and irritation rather than for clearing psoriasis, and itch is often what people most want addressed. Chickweed is a mild, edible plant with an excellent tolerability record, used as an adjunct alongside other treatment. There are no trials for psoriasis.

Calendula is one of the best-established topical anti-inflammatories in Western herbal medicine, used across rashes, burns, wounds and inflammatory skin states including psoriasis. The preclinical basis is real — triterpenoid esters, notably faradiol, account for the anti-inflammatory activity in animal oedema assays. No placebo-controlled trial has tested it in an actual inflammatory skin disease at a defined triterpenoid dose. Calendula serves as a gentle, well-tolerated base for a topical preparation rather than as a treatment for the plaques themselves.

Blue flag holds a specific place in the Western alterative tradition: it was given for skin disease understood as a problem of hepatic and lymphatic elimination, and psoriasis was among its named indications alongside acne and eczema. It is one of the more strongly acting alteratives, traditionally used in small doses and often in formula rather than alone. There is no experimental work behind the traditional role at all — the constituent analysis on record dates to 1881 ^{16Reference 16American Journal of Pharmacy · 1881The constituents of Iris versicolor — constituent analysis}.

Red clover is a gentle alterative of the same school as burdock, and often combined with it for chronic skin conditions. Red clover has a substantial modern research literature, but it concerns its isoflavones in menopausal symptoms and bone density rather than skin. Its psoriasis use is traditional, mild, and untested.

Neem is a major Ayurvedic skin herb, applied as oil or leaf preparation for a wide range of chronic skin disease including psoriasis. Neem has controlled human evidence — but it is for oral health, where neem mouthrinse performs comparably to chlorhexidine across three randomised trials. For skin, the use is traditional and extensive rather than trialled. Neem oil is a reasonable emollient carrier with a long record of topical use.

Used across South America for a broad range of skin complaints, psoriasis included — the species name impetiginosa records that dermatological reputation directly. The bark’s researched activity is antifungal and antineoplastic rather than anti-inflammatory, so the psoriasis use is not well matched to its known pharmacology.

In Brazilian practice the leaf and bark are used interchangeably for eczema and psoriasis, among a long list of skin and mucosal complaints ^{17,18Reference 17Taylor · 2005The Healing Power of Rainforest Herbs: A Guide to Understanding and Using Herbal MedicinalsReference 18Okpashi et al. · 2014Comparative effects of some medicinal plants: Anacardium occidentale, Eucalyptus globulus, Psidium guajava and Xylopia aethiopica extracts}. The shell carries urushiol, the contact allergen cashew shares with poison ivy and mango, while the leaf and bark used medicinally are a different matter. There is no psoriasis-specific testing.

Better known for wound healing and its antibacterial honey, manuka is used for general inflammatory skin complaints. Its evidence base concerns infected wounds and oral health rather than psoriasis, which is an immune rather than infective problem.

Milk thistle’s psoriasis use rests on alterative reasoning — that supporting liver function benefits chronic skin disease — rather than on any dermatological finding. Its evidence is good but hepatological.

Methotrexate, a mainstay systemic drug for severe psoriasis, is hepatotoxic, and silymarin’s best-evidenced role is protecting the liver during drug therapy. That is a question for the prescribing clinician rather than a self-directed combination.

Suma is the Brazilian “para todo” — for everything — used as a general restorative and, among many other things, for skin complaints. Its psoriasis use reflects the breadth of a tonic reputation rather than a specific dermatological tradition.

Rosewood is used in Amazonian practice as a skin remedy, with the essential oil applied for a range of dermatological complaints. A. rosaeodora is commercially endangered through over-harvest for the perfume trade, which is a real consideration before buying the oil.

Bitter melon is a food and medicine across Asia, Africa and the Caribbean, with skin complaints among its many traditional uses. Its serious research base is metabolic — blood glucose — not dermatological, and its use for skin reflects the breadth of traditional use rather than any psoriasis-specific evidence.