Evidence supporting the use of: Terpinen-4-ol
For the health condition: Lice

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Synopsis

Source of validity: Scientific
Rating (out of 5): 4

Terpinen-4-ol, a major active component of tea tree oil (Melaleuca alternifolia), has been studied for its efficacy against head lice (Pediculus humanus capitis). Several laboratory and clinical studies have demonstrated its insecticidal effects. Terpinen-4-ol is thought to act by disrupting the cell membranes of lice, leading to their death. Research indicates that products containing tea tree oil, particularly those standardized for terpinen-4-ol content, can kill both lice and their eggs (nits). For example, a 2012 randomized controlled trial found that a combination of tea tree oil and lavender oil was significantly more effective than a placebo in eradicating lice infestations. Additionally, in vitro studies have shown that terpinen-4-ol has ovicidal (egg-killing) activity, which is important for breaking the lice life cycle.

However, while there is moderate-to-strong scientific evidence supporting its use, most studies have evaluated combinations of tea tree oil with other essential oils, rather than terpinen-4-ol in isolation. Safety concerns, such as skin irritation or allergic reactions, also exist with topical use, especially in children. Nonetheless, based on current evidence, terpinen-4-ol is considered a scientifically validated ingredient for supporting lice treatment, though further high-quality studies are warranted to establish optimal dosing and safety profiles.

More about Terpinen-4-ol
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Products containing Terpinen-4-ol

We currently have no products on Caring Sunshine that contain this ingredient.