Tea tree oil (Melaleuca alternifolia) has been investigated for its potential use in treating scabies due to its antimicrobial and acaricidal properties. Several in vitro studies have demonstrated that tea tree oil and its main component, terpinen-4-ol, are toxic to Sarcoptes scabiei mites. For example, Walton et al. (2004, Archives of Dermatology) showed that tea tree oil was effective in killing scabies mites in laboratory settings. Furthermore, small clinical studies and case reports have suggested that topical application of tea tree oil formulations may reduce symptoms and mite burden in humans and animals with scabies.

The evidence base, however, is limited by the small number and size of clinical trials. A 2016 systematic review (Cameron et al., International Journal of Dermatology) concluded that tea tree oil shows promise as a topical treatment for scabies, especially in cases resistant to standard therapies, but highlighted the need for larger, well-designed randomized controlled trials. Tea tree oil is not a first-line, guideline-recommended treatment for scabies, but it is sometimes used adjunctively or in cases where conventional treatments are unavailable or contraindicated.

In summary, while tea tree oil is not yet an established standard of care, its use is supported by preliminary scientific evidence and laboratory studies, warranting further research.