Herb

    Oregon Grape

    Mahonia aquifolium

    TL;DR

    Oregon grape is a berberine-containing root used mainly as a topical for psoriasis, where small trials show modest plaque improvement. Oral use carries the same berberine interaction problems without the same evidence.

    Ideal For

    • People with mild plaque psoriasis wanting a topical adjunct
    • Those already using a dermatologist-supervised regimen

    Avoid If

    • You are pregnant or breastfeeding
    • You are giving it to an infant, due to bilirubin displacement risk
    • You take drugs metabolised by CYP3A4
    • You have liver disease

    Frequently Asked Questions

    Overview

    Oregon grape (Mahonia aquifolium) contains berberine, berbamine and oxyacanthine. Its best-supported use is topical: 10 percent Mahonia cream applied twice daily has been compared with placebo and with calcipotriol in small psoriasis trials, producing meaningful but smaller improvements than the prescription comparator, with good tolerability. A handful of open-label studies report reduced PASI scores over 12 weeks. Oral use is traditional for digestive complaints and infections, but the human evidence is essentially absent and the berberine content brings the same concerns that apply to berberine itself, including CYP3A4 inhibition and displacement of bilirubin, which is why it is contraindicated in newborns and pregnancy. Treat oral Oregon grape as an inferior, less standardised route to berberine.

    How It Works

    • Berberine alkaloids inhibit keratinocyte hyperproliferation, relevant to psoriasis plaques
    • Inhibits lipoxygenase, reducing inflammatory leukotriene production
    • Antimicrobial activity against several bacteria and fungi in vitro
    • Berberine inhibits CYP3A4, the source of most interaction risk

    Benefits & Outcomes

    No linked outcomes yet. Research is ongoing.

    Health Concerns Addressed

    Psoriasis

    condition
    Mixed evidence
    Limited
    Effectiveness 2/5

    Reasonable as a topical adjunct for mild plaque psoriasis. Do not use it orally for this purpose.

    Supporting Research
    5 studies

    Plant extracts for the topical management of psoriasis: a systematic review and meta-analysis

    Score: 7/10
    2013
    meta_analysis

    Deng S, May BH, Zhang AL +2 more

    Topical Mahonia aquifolium showed benefit for psoriasis severity, but the evidence was of low methodological quality.

    View source

    Berberine in the treatment of type 2 diabetes mellitus: a systematic review and meta-analysis

    Score: 7/10
    2015
    meta_analysis

    Lan J, Zhao Y, Dong F

    Berberine, the main alkaloid in Oregon grape, lowered fasting glucose and HbA1c in pooled trials.

    View source

    Berberine-containing plants: safety, drug interactions and contraindications

    Score: 6/10
    2019
    systematic_review

    Imenshahidi M, Hosseinzadeh H

    Berberine-containing botanicals inhibit CYP3A4 and are contraindicated in pregnancy and in neonates.

    View source

    Mahonia aquifolium in patients with psoriasis vulgaris: an intra-individual study

    Score: 4/10
    1999
    rct
    n=82

    Augustin M, Andrees U, Grimme H +2 more

    Mahonia ointment was less effective than dithranol but better tolerated in plaque psoriasis.

    View source

    Mahonia aquifolium ointment for mild to moderate psoriasis: a multicentre prospective open study

    Score: 3/10
    2005
    observational
    n=200

    Gulliver WP, Donsky HJ

    Most patients using Mahonia ointment for 12 weeks reported improvement in psoriasis severity.

    View source

    Safety Information

    Potential Side Effects

    Topical: burning, itching or rash in a minority. Oral: GI upset, nausea. Berberine alkaloids can cause diarrhoea and cramping.

    Contraindications

    Pregnancy, lactation, neonates and infants; concurrent CYP3A4-dependent medication.

    Drug Interactions

    • Inhibits CYP3A4, raising levels of statins, ciclosporin and many others
    • May add to the glucose-lowering effect of antidiabetic drugs
    • Displaces bilirubin from albumin, dangerous in neonates

    Pregnancy & Breastfeeding

    Pregnancy: likely_unsafe

    Breastfeeding: likely_unsafe

    Dosage Guidelines

    Dosage Used in Studies

    Consult healthcare provider

    Forms Compared

    Food & Timing

    Topical use is unaffected by food. Oral tincture is traditionally taken before meals.

    Medical Disclaimer

    The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.

    Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.