Essential oils are the vehicle for the application of aromatherapy. By nature, they are very concentrated and as such products with strong active ingredients, if used thoughtlessly by people not specialized in the field of aromatherapy, they can cause problems. Therefore, it is important to be used in a responsible way and by people of knowledge, meaning something only an aromatherapist can do so. Also, it is good to know that essential oils are not permitted during the first 4 months of pregnancy, during breastfeeding, in babies up to 4 months old, and people who have recently been operated.