Cutaneous Contact Urticaria to Pyrethrum–Real?, Common?, or Not Documented?: An Evidence-Based Approach

Abstract

Reports suggest that pyrethrum, the insecticidally active extract from Chrysanthemum cinerariifolium, can induce Type I hypersensitivity reactions in humans. Using knowledge of pyrethrum chemistry and an evidence-based analysis of literature, whether current refined pyrethrum induces and/or elicits skin manifestations of contact urticaria was assessed. Current extraction and refinement techniques suggest that refined pyrethrum lacks the presence of significant, if any, proteins speculated to induce Type I hypersensitivity. Our interpretation suggests that no reports of Type I reactions presented in the literature fulfill the criteria for immunologic contact urticaria. Future patient testing with current commercial material should clarify its Type I immunologic potential, if any.

Keywords :

• Allergic conjunctivitis
• Allergic rhinitis
• Anaphylaxis
• Asthma
• Compositae
• Contact urticaria
• Cross-sensitivity
• Insecticide
• Pesticide
• Pyrethrin
• Pyrethrum
• Type I hypersensitivity

Notes

¹The PJV is a consortium of pyrethrins growers, refiners, and end use product marketers that was formed to address the data requirements for Reregistration of pyrethrins with the USEPA.