The ingestion of essential oils is not recommended unless under the guidance of a qualified and experienced aromatherapist. Essential oils are very concentrated and have been known to cause damage to mucous membranes as well as reactions when use inappropriately.
Please see this interview with Robert Tisserand:
https://roberttisserand.com/2015/08/robert-tisserand-interviewed-on-ingestion-dilution-and-other-safety-issues/
You may also wish to check out this guide on essential oils from our blog, there is some good safety info here!