Snakeroot is a common name applied to several different plant species, including Rauwolfia serpentina (Indian snakeroot), Aristolochia serpentaria (Virginia snakeroot), and Eupatorium rugosum (white snakeroot), among others. In traditional herbal medicine, especially within Native American and Ayurvedic practices, various forms of snakeroot have been used topically or as decoctions for skin-related issues such as rashes, hives, and other inflammatory skin conditions. The rationale behind these uses is primarily anecdotal or based on traditional knowledge systems rather than modern pharmacological studies.

Scientific evidence supporting the use of "snakeroot" (regardless of species) specifically for rashes and hives is minimal to non-existent. No well-designed clinical trials or laboratory studies have established efficacy for this indication, and most references to its use for skin conditions are found in ethnobotanical or historical texts. Some species, like Rauwolfia serpentina, are better known for their cardiovascular and sedative effects, while others have been traditionally applied to wounds or bites. The lack of specificity regarding which snakeroot species is being used further limits the ability to assess efficacy or safety.

In summary, the use of snakeroot for rashes and hives is primarily justified by traditional use with extremely limited scientific validation available. Caution is advised due to the potential toxicity of some snakeroot species.