Efficacy evaluation of a topical formulation containing green tea and willow bark extract for acne and post-acne mark reduction in Indian subjects: a double-blind clinical study

Authors

  • Ravi Kant Shukla Department of R&D, Hindustan Unilever Ltd., Mumbai, India
  • Rahul Malik Department of R&D, Hindustan Unilever Ltd., Mumbai, India
  • Ratna Upadhyay Department of R&D, OZiva, Zywie Ventures Ltd., Mumbai, India
  • Supriya Punyani Department of R&D, Hindustan Unilever Ltd., Mumbai, India

DOI:

https://doi.org/10.18203/issn.2455-4529.IntJResDermatol20263741

Keywords:

Acne, Acne marks, Acne-prone skin, Clinical study, Melanin index, PIH, Post-inflammatory hyperpigmentation

Abstract

Background: Consumers with acne-prone skin often experience recurring pimples, inflammation, uneven texture and stubborn post-acne dark marks linked to post-inflammatory hyperpigmentation (PIH). These concerns affect skin clarity and even tone, highlighting the need for gentle, effective topical solutions. This clinical study evaluates the efficacy of a topical formulation containing green tea extract actives (5%) and willow bark extract (2%) in reducing acne and acne marks over a 7-day period.

Methods: A double-blind, non-comparative clinical study was conducted on 36 Indian subjects (18 males, 18 females; aged 18–35 years) with mild-to-moderate acne and oily to combination skin. The test product was applied twice daily for 7 days. Efficacy was assessed using the Michaelsson acne severity index, lesion analysis, mexametry for PIH and subject self-evaluation. Safety was evaluated through dermatological assessment of irritation parameters. Measurements were recorded at baseline, day 1, day 3 and day 7.

Results: The test product demonstrated a time-dependent reduction in melanin index associated with acne-induced PIH, with mean reductions of 0.11%, 0.50% and 0.77% at day 1, day 3 and day 7, respectively. By Day 7, improvement in PIH-related acne marks was observed in up to 100% of subjects. Acne severity significantly reduced (-25.72%, p<0.001) by day 7, with notable decreases in papule and pustule redness and size and in comedones size. No adverse events or irritation were reported and 100% of subjects agreed the product reduced acne and acne marks.

Conclusions: The formulation effectively reduced acne, PIH-related acne marks and melanin index within 7 days, with good tolerability and no reported irritation or adverse events.

 

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Published

2026-10-23

How to Cite

Shukla, R. K., Malik, R., Upadhyay, R., & Punyani, S. (2026). Efficacy evaluation of a topical formulation containing green tea and willow bark extract for acne and post-acne mark reduction in Indian subjects: a double-blind clinical study. International Journal of Research in Dermatology, 12(6), 626–632. https://doi.org/10.18203/issn.2455-4529.IntJResDermatol20263741

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Original Research Articles