While some advocate the ingestion of essential oils for therapeutic purposes, licensed aromatherapy professionals do not recommend self-prescription due to the highly toxic nature of some essential oils. Some very common oils like eucalyptus are extremely toxic when taken internally. Doses as low as 2 mL have been reported to cause clinically significant symptoms and severe poisoning can occur after ingestion of as little as 4 mL. A few reported cases of toxic reactions like liver damage and seizures have occurred after ingestion of sage, hyssop, thuja and cedar oils. Accidental ingestion may happen when oils are not kept out of reach of children. As with any bioactive substance, an essential oil that may be safe for the general public could still pose hazards for pregnant and lactating women.
You can use essential oils in any number of ways. For example, add them to body lotions or carrier oils, and then apply them topically. Try enhancing a facial toner, shampoo, or conditioner with essential oils. Or incorporate them into liquid soap, toothpaste, or mouthwash. You can also diffuse or spritz the oils throughout a room or pour them into a bath.