Oregon Grape
At a glance
- Best for
- people with mild plaque psoriasis seeking a topical option
- Typical dose
- 10% cream topically twice daily; 500–3000 mg/day dried root orally
- Time to effect
- Weeks (topical psoriasis)
- Main caution
- berberine content inhibits CYP3A4/2D6 and P-glycoprotein, raising levels of many drugs; avoid in pregnancy and infants
What is it
Oregon grape ( Mahonia aquifolium , also classified as Berberis aquifolium ) is an evergreen shrub native to the Pacific Northwest of North America whose yellow inner bark and root have a long ethnobotanical history of use by Indigenous peoples and in Western herbalism. The plant is rich in isoquinoline alkaloids - principally berberine, berbamine, and oxyacanthine - which are responsible for its characteristic bitter taste, yellow colour, and most of its pharmacological activity. Modern supplement use centres on standardised root and bark extracts, often quantified by berberine content, marketed for digestive, skin, and antimicrobial support.
Is it worth it for you?
Worth considering if…
- You have mild plaque psoriasis and want to trial a 10% topical cream
- You are not pregnant, breastfeeding, or dosing an infant
- You can separate oral use from interacting medications
Probably skip if…
- You are pregnant or breastfeeding (kernicterus risk in neonates)
- You take cyclosporine, statins, or macrolide antibiotics without separation
- You expect proven systemic antimicrobial or digestive benefit
Evidence at a glance
| Goal | Evidence | Effect | Best fit | Time |
|---|---|---|---|---|
| plaque psoriasis (topical) | Limited Evidence | Modest improvement in plaque severity | adults with mild-to-moderate plaque psoriasis | Weeks |
| glycemic and lipid effects (via berberine) | Limited Evidence | Modest reductions in glucose and lipids | adults with elevated glucose or lipids using berberine-standardized extracts | Weeks |
| antimicrobial and antifungal effects | Mixed Evidence | Unclear in humans | not established | Unclear |
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
plaque psoriasis (topical)
Disease adjunctA small clinical evidence base supports 10% Mahonia aquifolium cream for reducing plaque severity in mild-to-moderate psoriasis. Effects are modest and studies are limited in size and quality.
Bottom line: Topical 10% cream may modestly improve mild plaque psoriasis.
glycemic and lipid effects (via berberine)
Biomarker supportOregon grape's main alkaloid, berberine, lowers fasting glucose, HbA1c, and LDL in meta-analyses of berberine trials. This evidence is for purified berberine, not Oregon grape extract specifically, and reflects biomarker changes rather than tested clinical outcomes.
Bottom line: Berberine content may shift glucose and lipid markers, but this is extrapolated from purified berberine, not Oregon grape itself.
antimicrobial and antifungal effects
Mechanism onlyBerberine-containing extracts show antibacterial and antifungal activity in laboratory studies. There is little controlled human evidence that oral or topical Oregon grape treats clinical infections.
Bottom line: Antimicrobial activity is shown in the lab but not demonstrated clinically.
How to take it
- Typical dose
- Topical: 10% Mahonia aquifolium cream twice daily. Oral: 500–3000 mg/day dried root, or extract delivering 200–500 mg berberine-equivalent alkaloids
- Timing
- topical applied to affected skin; oral split through the day
- With food
- oral with food to reduce GI upset
- How long to try
- Topical: trial several weeks. Oral systemic use generally limited to a few weeks
What to track
- psoriasis plaque severity and itch
- skin irritation from the cream
- digestive symptoms
- blood glucose if diabetic
Safety
Common side effects
GI upset, nausea, bitter aftertaste, skin irritation with topical use
Serious risks
- kernicterus risk in neonates from berberine displacing bilirubin
Who should avoid it
- pregnancy and breastfeeding
- infants
- people requiring narrow-therapeutic-index drugs metabolized by CYP3A4/2D6
Pregnancy & breastfeeding
Contraindicated in pregnancy and lactation; berberine crosses the placenta and can raise neonatal kernicterus risk.
Interactions
berberine inhibits CYP3A4 and P-glycoprotein, raising cyclosporine levels
CYP3A4/P-gp inhibition can raise plasma drug levels; separate dosing
additive glucose-lowering effect
possible additive blood-pressure lowering
Choosing a product
Look for
- standardized to berberine-equivalent alkaloids
- names Mahonia/Berberis aquifolium and plant part
- 10% strength for topical psoriasis creams
Be skeptical of
- 'natural antibiotic'
- broad 'detox' or infection-cure claims
- use in pregnancy or infants
References by claim
plaque psoriasis (topical)
glycemic and lipid effects (via berberine)
Track Oregon Grape with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.