15,16-Dihydrotanshinone I is a bioactive compound isolated from the roots of Salvia miltiorrhiza (Danshen), a traditional Chinese medicinal herb. Recent scientific studies have provided evidence supporting its potential use in the treatment of acne. Specifically, in vitro research has demonstrated that 15,16-Dihydrotanshinone I exhibits significant antibacterial activity against Propionibacterium acnes (recently renamed Cutibacterium acnes), the bacterium implicated in the pathogenesis of acne vulgaris. For example, a study published in Phytomedicine (2012) found that this compound not only inhibited the growth of C. acnes but also reduced inflammation by suppressing pro-inflammatory cytokine production in keratinocytes.

Furthermore, 15,16-Dihydrotanshinone I has demonstrated anti-inflammatory properties, which could help mitigate the inflammatory lesions characteristic of moderate to severe acne. However, while preclinical studies (cell-based and animal models) are promising, there is a lack of high-quality clinical trials directly evaluating its efficacy and safety in human patients with acne. Therefore, the current evidence base is moderate: there is scientific support from laboratory and animal research, but human clinical data are still lacking. Until such studies are conducted, its use for acne remains experimental but scientifically plausible.