Herbal medicines containing valerian essential oil are usually available in liquid forms to be taken by mouth or used as bath additives. Valerian essential oil may also be found in combination with other herbal substances in some herbal medicines. https://www.ema.europa.eu/en/documents/herbal-summary/valerian-essential-oil-summary-public_en.pdf
Valerian essential oil is mainly used for aromatherapy and is not intended for internal use. Even food-grade essential oils used for flavoring should never be taken by mouth. https://www.verywellhealth.com/what-you-need-to-know-about-valerian-88336
This pdf is about extraction of Valerian root (by ethanol 70%).
But my question is about the reason of NOT taking Valerian essential oil orally and what is the difference between this ectract compound (maybe) and it's essential oil.