Centella Asiatica Extract

• Measured on: facial erythema and general wound appearance after ablative laser resurfacing, physician-graded against a placebo-treated half-face, with instrument erythema index as the supporting measure.
• One trial tests the extract on its own against its own vehicle on human facial skin with a proper visit schedule.
• Thirty people with acne scars had full-face 2940 nm Er:YAG resurfacing, then applied 0.05% ECa 233 gel — a standardised Centella asiatica extract — to one half-face and an identical placebo gel to the other, four times daily for the first week and twice daily thereafter, assessed at baseline, days 2, 4 and 7, then every two weeks through the first month and monthly to three.
• Physician-graded erythema was significantly better on the treated side at day 2 and remained so at days 4 and 7, as did general wound appearance, with crusting separating at day 2 and the instrument erythema index lower across the whole follow-up.
• Day 2 was the first post-baseline visit, so the true onset may be faster than the bucket says.
• Two limits on how far this travels.
• The skin had been ablated, so this dates recovery from a controlled wound rather than the calming of an ordinary reactive face — which is also why the strong wound-healing literature behind this row cannot be read as a cosmetic timeline.
• And as the base's own solubility note says, the INCI covers everything from a water infusion to a triterpene concentrate; ECa 233 is at the concentrate end, a defined asiaticoside-and-madecassoside standard, so a generic centella water low in a toner is not the material that was tested.
• The barrier claim is separately weaker: the only study is 30 batik workers with dry hands given a centella cream or a ceramide cream, comparator-controlled with no vehicle arm, reporting at 2 and 4 weeks.

Damkerngsuntorn W, Rerknimitr P, Panchaprateep R, Tangkijngamvong N, Kumtornrut C, Kerr SJ, Asawanonda P, Tantisira MH, Khemawoot P. 'The Effects of a Standardized Extract of Centella asiatica on Postlaser Resurfacing Wound Healing on the Face: A Split-Face, Double-Blind, Randomized, Placebo-Controlled Trial.' J Altern Complement Med. 2020;26(6):529-536. PMID:32310680 (DOI:10.1089/acm.2019.0325). Barrier clause: PMID:34214362 (Centella cream vs ceramide cream, 30 batik workers, comparator-controlled, reads at 2 and 4 weeks).