Ingredient · dataset v56
St. John's Wort Oil and fungal acne
May trigger · Limited evidence
Why it's a potential trigger
Usually sold as flower material steeped in a fatty base oil such as sunflower or olive oil; the base is food for Malassezia yeast, so the infusion reads as food too.
Infusion-form entry: the verdict follows the fatty carrier base, not the flower. Not individually feeding-tested.
Evidence strength
Limited evidence (1/3)
Function
Oil
Plant oils: triglyceride oils and butters the yeast harvests after its enzymes split them.
Also listed as
Hypericum Perforatum Oil, Hypericum Perforatum Flower Oil
Products without this ingredient
- Selsun Blue Medicated Anti-Dandruff Shampoo (Selenium Sulfide 1%)
- SEEN Body Wash Fragrance Free 10 fl oz
- The Ordinary Glucoside Foaming Cleanser
- Acure Dry Shampoo, Non Aerosol, Clean, 100% Vegan 1.7 oz Travel Size
- Lily Lolo Mineral Foundation SPF 15 In The Buff 10 g
- Aztec Secret Indian Healing Clay 1 lb New Version 2
Related oil
- Acai Fruit Oil — May trigger · Moderate evidence
- Apricot Kernel Oil — May trigger · Moderate evidence
- Argan Oil — May trigger · Moderate evidence
- Avocado Oil — May trigger · Moderate evidence
- Babassu Seed Oil — May trigger · Moderate evidence
- Baobab Seed Oil — May trigger · Moderate evidence
- Black Currant Seed Oil — May trigger · Moderate evidence
- Borago Officinalis Seed Oil — May trigger · Moderate evidence
Sources
- Brunke & Hube 2006 — MfLIP1 extracellular lipase hydrolyses Tweens (Microbiology)
- Mayser et al. 1995 — ester hydrolysis depends on alcohol moiety (Acta Derm Venereol)
- EU CosIng database — search the INCI name
Last reviewed: 2026-10-13 (dataset v56).
Questions
Does St. John's Wort Oil trigger fungal acne?
We flag it as a potential trigger (limited evidence). That means it belongs to a class the Malassezia yeast is known to feed on — not that every product with it will cause a flare. Concentration, formulation and individual skin chemistry matter.
Does St. John's Wort Oil feed Malassezia?
Yes: we flag St. John's Wort Oil as a potential trigger (limited evidence). It belongs to a class Malassezia is known to feed on — not a claim that every product with it causes a flare. Concentration, formulation and individual skin chemistry matter.
How confident is this call?
Limited evidence: Usually sold as flower material steeped in a fatty base oil such as sunflower or olive oil; the base is food for this yeast, so the infusion reads as food too.
Is this medical advice?
No. We screen ingredient lists; we never diagnose, treat, or certify products. When in doubt, ask a dermatologist.
Check a full list containing St. John's Wort Oil →
Not medical advice: we screen ingredient lists for potential triggers — we never diagnose, treat, or certify products. Dataset v56.