Houttuynia Cordata Extract

Houttuynia cordata extract is typically used at low-to-moderate levels (often ~0.1–5%) as a soothing/anti-inflammatory botanical, and most users tolerate it well in leave-on products. However, as a complex plant extract containing multiple bioactive compounds, it carries a non-trivial risk of irritant or allergic contact dermatitis in highly reactive or eczema-prone patients, especially with frequent, multi-product exposure. For safety in sensitive populations, I rate it as gentle but not “very gentle” because botanicals are a common source of unpredictable reactions despite a calming marketing profile. Safety Notes: In commercial skincare, Houttuynia cordata extract is often used at very low levels (~0.01–0.1%) as a secondary soothing/antioxidant botanical in emulsions and cleansers, consistent with typical supplier use-level guidance for standardized extracts. Many K-beauty toners/serums list it as a featured calming ingredient and commonly land in the ~1–5% range, while consumer-available “single-ingredient/one-thing” essences, ampoules, and concentrated watery extracts frequently reach ~10–20% (with higher percentages generally being diluted extract solutions rather than pure dry extract). Leave-on products tend to sit higher than rinse-off due to contact time, but both forms exist across the low end of the range.