Plectranthus amboinicus, also known as Indian borage or Cuban oregano, has a long history of use in traditional medicine systems, particularly in South and Southeast Asia, for a variety of skin conditions, including eczema. Traditional healers have used the crushed leaves topically for their purported soothing, anti-inflammatory, and antimicrobial effects, which are thought to help alleviate itching and irritation associated with eczema. Ethnobotanical records and surveys frequently list P. amboinicus as a folk remedy for skin ailments, though the specifics of preparation and application can vary between cultures.

From a scientific perspective, preliminary in vitro studies have identified several bioactive compounds in P. amboinicus, such as carvacrol and thymol, that exhibit anti-inflammatory and antimicrobial properties. However, direct evidence from clinical trials or well-designed animal studies specifically investigating its efficacy for eczema is lacking. Most available scientific literature on P. amboinicus pertains to its general antimicrobial and anti-inflammatory effects rather than its application in eczema treatment.

In summary, the use of P. amboinicus for eczema is primarily justified by its traditional and ethnomedicinal usage, with only low-level scientific evidence supporting its potential benefits for skin inflammation. High-quality clinical research is needed to confirm safety and efficacy for this specific condition.