Plant-induced seizures: reappearance of an old problem

Several plant-derived essential oils have been known for over a century to have epileptogenic properties. We report three healthy patients, two adults and one child, who suffered from an isolated generalized tonic-clonic seiz ure and a generalized tonic status, respectively, related to the absorption of several of these oils for therapeutic purposes. No other cause of epile psy was found, and outcome was good in the two adult cases, but the course has been less favorable in the child. A survey of the literature shows esse ntial oils of 11 plants to be powerful convulsants (eucalyptus, fennel, hys sop, pennyroyal, rosemary, sage, savin, tansy, thuja, turpentine, and wormw ood) due to their content of highly reactive monoterpene ketones, such as c amphor, pinocamphone, thujone, cineole, pulegone, sabinylacetate, and fench one. Our three cases strongly support the concept of plant-related toxic se izure. Nowadays the wide use of these compounds in certain unconventional m edicines makes this severe complication again possible.