Plectranthus amboinicus, commonly known as Indian borage or Cuban oregano, has a longstanding presence in traditional medicine systems, particularly in South Asia, Africa, and the Caribbean. In these traditions, the leaves are often crushed and applied topically to the skin to relieve itching caused by insect bites, rashes, or other minor irritations. The traditional use is attributed to its cooling effect and the aromatic oils present in the leaves, which are believed to soothe the skin.

However, scientific studies directly evaluating the efficacy of Plectranthus amboinicus for the treatment of itching (pruritus) are limited. While some research has identified the presence of bioactive compounds in the plant, such as thymol and carvacrol, which have anti-inflammatory and antimicrobial properties, there is a lack of clinical trials or robust pharmacological studies specifically supporting its anti-pruritic effects. The available scientific evidence is mostly indirect, focusing on general anti-inflammatory or wound-healing properties rather than relief from itching itself.

In summary, the use of Plectranthus amboinicus for itching is primarily justified by traditional practices rather than scientific validation. The overall quality of evidence supporting this specific use is low (rated 1), and more targeted research would be needed to establish its efficacy and safety for itching relief.