Different in vivo administration routes of essential oil for various therapies: A review

Essential oils derived from aromatic and non-aromatic plant sources, are recognized for their in vivo potential therapeutic benefits, including anti-oxidant, anti-inflammatory, anti-cancer, immunomodulatory and other regulatory roles by the scientific community. However, translation of such in vivo therapeutic application in clinical field is not yet available. This study examines the pre-clinical scientific studies on varied administration methods of essential oils for therapeutic purposes. The focus of this study is to explore the different administration routes, which are crucial for optimizing the delivery of these bioactive compounds for internal administration and improving their therapeutic effectiveness. Traditional and innovative methods, such as inhalation, dermal application, oral ingestion, intraperitoneal injection, and intravenous infusion are investigated. Each route has its advantages and challenges, which may impact the bioavailability, systemic distribution and toxicity of essential oils. However, such comparative pharmacokinetic and toxicity studies are lacking for the essential oils. The available basic information regarding in vivo bioavailability and toxic reactions of essential oils are discussed briefly in this review. The research findings have significant implications for developing targeted and personalized essential oil treatments, advancing integrative medicine and complementary therapy approaches. The analysis of various in vivo therapeutic study findings implies that a promising therapeutic efficiency can be achieved with essential oils at different dose ranges for different routes of administrations. The comparative analysis on therapeutic effects of different routes of administration and methods essential oil extraction are lacking. The bioavailability and toxicity studies are also limited for these therapeutic studies. Furthermore, the detailed molecular mechanism of in vivo therapeutic actions is not yet established in the studies. Ultimately, this investigation adds to the expanding knowledge base on essential oil administration routes, providing valuable guidance for healthcare professionals and researchers in the field of natural medicine. However, extensive in vivo pre-clinical studies are warranted for translation of essential oil therapy to clinical usage. Also all the traditional uses of essential oil for therapy must be validated via scientific studies.