Echinacea‐associated anaphylaxis

Abstract

A woman with atopy experienced anaphylaxis after taking, among other dietary supplements, a commercial extract of echinacea. Hypersensitivity was confirmed by skinprick and RAST testing. Regular ingestion of echinacea by up to 5% of surveyed patients with atopy, combined with detection of echinacea‐binding IgE in atopic subjects (19% by skin testing; 20% with moderate to strong reactivity by RAST testing), raises the possibility of severe allergic reactions, even with first‐time use, due to cross‐reactivity with other structurally similar allergens. Patients with atopy should be cautioned about the risk of developing life‐threatening reactions to complementary medicines, including echinacea.