The Australian cushion bush ( Leucophyta brownii ) of the Compositae family of plants has become a popular pot and container plant. The plant produces the sesquiterpene lactone allergen calocephalin. The well-known sesquiterpene lactone pseudoivalin and its derivative pseudoivalin acetate, as well as calocephalin and tomentosin, were confirmed to be sensitizers, whereas leucophytalin A and 4?-hydroxy-5?H,10?H-1,11(13)-guaidien-8?,12-olide were shown to be allergenic for the first time.
