The use of Hedyotis species (commonly referred to as "Oldenlandia" in traditional medicine texts) for acne is primarily based on traditional practices, particularly within Traditional Chinese Medicine (TCM) and other Asian herbal systems. Hedyotis diffusa is one of the most commonly used species, often prescribed for its purported "heat-clearing" and detoxifying properties, which in TCM theory relate to conditions like acne that are thought to involve internal "heat" or inflammation. Traditional formulas containing Hedyotis are used to treat various skin eruptions, boils, and sores, including acne.

However, scientific evidence supporting the efficacy of Hedyotis for acne is limited. There are a few in vitro and animal studies suggesting antimicrobial and anti-inflammatory properties of Hedyotis extracts, but direct clinical studies on acne patients are lacking. No rigorous, peer-reviewed human trials have established its safety or effectiveness for this indication. Thus, while its use is well-documented in traditional medicine, the scientific validation remains minimal and largely theoretical, justifying a low evidence rating.