Though many herbs, essential oils, and carrier oils have few reported side effects, allergies and reactions may occur with anyone, at any time. It is important to ask about allergies (particularly to ragweed and other seasonal allergies) during the client consultation, prior to using or recommending any plants. Be aware that anyone can be allergic to anything at any time, regardless of allergy history or past allergy test results. Patch testing is always a good idea. Phototoxicity is another legitimate concern. Be careful with herbs in the citrus or mint families, topical application of St. John’s wort, any herbs containing …Read more »