Abstract

Dermatitis due to ayan wood (Distemonanthus benthamianus) is described. The main clinical features appear to be an initial slight itch followed later by intense erythema and pruritus often precipitated by washing. Previous work on the extractives of the wood have suggested that there may be two varieties of ayan, one rich in oxyayanin-B and the other rich in distemonanthin. Two other flavonoids, oxyayanin-A and ayanin, were found in both varieties.

Patch tests were carried out using the various extractives and the whole wood, and the results suggest that only oxyayanin-A and oxyayanin-B contribute to the sensitizing action. One type of ayan wood contains a preponderance of oxyayanin-B and the other a preponderance of distemonanthin; there is no quick method of distinguishing between the two, but it is the former which seems more liable to sensitize.