The study was conducted towards 60 participants aged 20-40 years with mild to moderate acne. Herbal extracts used for the intervention included: mangosteen, Lithospermum officinale, Tribulus terrestris L., and Houttunynia cordata Thunb extract. Participants were blinded and randomly allocated to the intervention or control group and followed instruction to use the cleanser containing the herbal extracts twice per day every morning and evening. Researchers assessed efficacy and safety profiles of the intervention using acne inflammatory and non-inflammatory lesion counts and a skin biopsy. Results showed a significant decrease in both lesion types in the intervention group at week 8, with a 56% reduction in inflammatory lesions (p = 0.005) and a 36% reduction in non-inflammatory lesions (p = 0.028). A total of 9 mild adverse effects were reported from participants who experienced either dryness, burning, or prickling sensations following application of the herbal extracts. Immunohistochemistry also revealed a significant decrease in the expression of mediators IL-1a, IL-8 and keratin 6, which are responsible for inflammation and abnormal follicular keratinization in acne lesions. Researchers concluded herbal extracts as having significant clinical efficacy in treating patients with mild to moderate acne.