The coumarin herniarin as a sensitizer in German chamomile [Chamomilla recutita (L.) Rauschert, Compositae].
BACKGROUND
Although German chamomile (Chamomilla recutita) is considered a weak sensitizer, recent studies have shown several possible non-sesquiterpene lactone allergens in tea (infusions) from the plant.


OBJECTIVE
The aim of this study was to report the results of patch testing with herniarin (7-methoxycoumarin), which is one of the possible coumarin allergens in chamomile.


METHODS
Between 1991 and 2009, selected patients with known or suspected Compositae contact allergy were patch tested with herniarin 1% petrolatum.


RESULTS
Among 36 patients tested, there was one positive and three doubtful positive reactions to herniarin. All 4 patients had a relevant contact allergy to German chamomile, whereas the majority of the remaining 32 patients had chamomile allergy of unknown relevance.


CONCLUSIONS
The clinical results suggest that herniarin indeed is one of the non-sesquiterpene lactone sensitizers in German chamomile and that sensitization may occur through, for example, external use of chamomile tea or use of chamomile-containing topical herbal remedies.
Paulsen
Evy
E
Department of Dermatology and Allergy Centre, Odense University Hospital, University of Southern Denmark, DK-5000 Odense C, Denmark. evy.paulsen@ouh.regionsyddanmark.dk
Otkjaer
Aksel
A
Andersen
Klaus E
KE
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001628:Beverages / Q000009:adverse effects*; D016572:Cyclosporine / Q000627:therapeutic use; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology*; D004485:Eczema / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology*; D005260:Female; D006801:Humans; D031168:Matricaria / Q000009:adverse effects*; D008875:Middle Aged; D010328:Patch Tests; D014468:Umbelliferones / Q000009:adverse effects* / Q000276:immunology
D000305:Adrenal Cortex Hormones; D000900:Anti-Bacterial Agents; D014468:Umbelliferones; C007929:herniarin; D016572:Cyclosporine